typeck.c (cp_truthvalue_conversion): Add tsubst_flags_t parameter and use it in calls...
[official-gcc.git] / gcc / ipa-inline.c
blob7fcb20081727b9e7d39738f6f0cc44788e3e9220
1 /* Inlining decision heuristics.
2 Copyright (C) 2003-2019 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* Inlining decision heuristics
23 The implementation of inliner is organized as follows:
25 inlining heuristics limits
27 can_inline_edge_p allow to check that particular inlining is allowed
28 by the limits specified by user (allowed function growth, growth and so
29 on).
31 Functions are inlined when it is obvious the result is profitable (such
32 as functions called once or when inlining reduce code size).
33 In addition to that we perform inlining of small functions and recursive
34 inlining.
36 inlining heuristics
38 The inliner itself is split into two passes:
40 pass_early_inlining
42 Simple local inlining pass inlining callees into current function.
43 This pass makes no use of whole unit analysis and thus it can do only
44 very simple decisions based on local properties.
46 The strength of the pass is that it is run in topological order
47 (reverse postorder) on the callgraph. Functions are converted into SSA
48 form just before this pass and optimized subsequently. As a result, the
49 callees of the function seen by the early inliner was already optimized
50 and results of early inlining adds a lot of optimization opportunities
51 for the local optimization.
53 The pass handle the obvious inlining decisions within the compilation
54 unit - inlining auto inline functions, inlining for size and
55 flattening.
57 main strength of the pass is the ability to eliminate abstraction
58 penalty in C++ code (via combination of inlining and early
59 optimization) and thus improve quality of analysis done by real IPA
60 optimizers.
62 Because of lack of whole unit knowledge, the pass cannot really make
63 good code size/performance tradeoffs. It however does very simple
64 speculative inlining allowing code size to grow by
65 EARLY_INLINING_INSNS when callee is leaf function. In this case the
66 optimizations performed later are very likely to eliminate the cost.
68 pass_ipa_inline
70 This is the real inliner able to handle inlining with whole program
71 knowledge. It performs following steps:
73 1) inlining of small functions. This is implemented by greedy
74 algorithm ordering all inlinable cgraph edges by their badness and
75 inlining them in this order as long as inline limits allows doing so.
77 This heuristics is not very good on inlining recursive calls. Recursive
78 calls can be inlined with results similar to loop unrolling. To do so,
79 special purpose recursive inliner is executed on function when
80 recursive edge is met as viable candidate.
82 2) Unreachable functions are removed from callgraph. Inlining leads
83 to devirtualization and other modification of callgraph so functions
84 may become unreachable during the process. Also functions declared as
85 extern inline or virtual functions are removed, since after inlining
86 we no longer need the offline bodies.
88 3) Functions called once and not exported from the unit are inlined.
89 This should almost always lead to reduction of code size by eliminating
90 the need for offline copy of the function. */
92 #include "config.h"
93 #include "system.h"
94 #include "coretypes.h"
95 #include "backend.h"
96 #include "target.h"
97 #include "rtl.h"
98 #include "tree.h"
99 #include "gimple.h"
100 #include "alloc-pool.h"
101 #include "tree-pass.h"
102 #include "gimple-ssa.h"
103 #include "cgraph.h"
104 #include "lto-streamer.h"
105 #include "trans-mem.h"
106 #include "calls.h"
107 #include "tree-inline.h"
108 #include "profile.h"
109 #include "symbol-summary.h"
110 #include "tree-vrp.h"
111 #include "ipa-prop.h"
112 #include "ipa-fnsummary.h"
113 #include "ipa-inline.h"
114 #include "ipa-utils.h"
115 #include "sreal.h"
116 #include "auto-profile.h"
117 #include "builtins.h"
118 #include "fibonacci_heap.h"
119 #include "stringpool.h"
120 #include "attribs.h"
121 #include "asan.h"
123 typedef fibonacci_heap <sreal, cgraph_edge> edge_heap_t;
124 typedef fibonacci_node <sreal, cgraph_edge> edge_heap_node_t;
126 /* Statistics we collect about inlining algorithm. */
127 static int overall_size;
128 static profile_count max_count;
129 static profile_count spec_rem;
131 /* Return false when inlining edge E would lead to violating
132 limits on function unit growth or stack usage growth.
134 The relative function body growth limit is present generally
135 to avoid problems with non-linear behavior of the compiler.
136 To allow inlining huge functions into tiny wrapper, the limit
137 is always based on the bigger of the two functions considered.
139 For stack growth limits we always base the growth in stack usage
140 of the callers. We want to prevent applications from segfaulting
141 on stack overflow when functions with huge stack frames gets
142 inlined. */
144 static bool
145 caller_growth_limits (struct cgraph_edge *e)
147 struct cgraph_node *to = e->caller;
148 struct cgraph_node *what = e->callee->ultimate_alias_target ();
149 int newsize;
150 int limit = 0;
151 HOST_WIDE_INT stack_size_limit = 0, inlined_stack;
152 ipa_size_summary *outer_info = ipa_size_summaries->get (to);
154 /* Look for function e->caller is inlined to. While doing
155 so work out the largest function body on the way. As
156 described above, we want to base our function growth
157 limits based on that. Not on the self size of the
158 outer function, not on the self size of inline code
159 we immediately inline to. This is the most relaxed
160 interpretation of the rule "do not grow large functions
161 too much in order to prevent compiler from exploding". */
162 while (true)
164 ipa_size_summary *size_info = ipa_size_summaries->get (to);
165 if (limit < size_info->self_size)
166 limit = size_info->self_size;
167 if (stack_size_limit < size_info->estimated_self_stack_size)
168 stack_size_limit = size_info->estimated_self_stack_size;
169 if (to->inlined_to)
170 to = to->callers->caller;
171 else
172 break;
175 ipa_fn_summary *what_info = ipa_fn_summaries->get (what);
176 ipa_size_summary *what_size_info = ipa_size_summaries->get (what);
178 if (limit < what_size_info->self_size)
179 limit = what_size_info->self_size;
181 limit += limit * param_large_function_growth / 100;
183 /* Check the size after inlining against the function limits. But allow
184 the function to shrink if it went over the limits by forced inlining. */
185 newsize = estimate_size_after_inlining (to, e);
186 if (newsize >= ipa_size_summaries->get (what)->size
187 && newsize > param_large_function_insns
188 && newsize > limit)
190 e->inline_failed = CIF_LARGE_FUNCTION_GROWTH_LIMIT;
191 return false;
194 if (!what_info->estimated_stack_size)
195 return true;
197 /* FIXME: Stack size limit often prevents inlining in Fortran programs
198 due to large i/o datastructures used by the Fortran front-end.
199 We ought to ignore this limit when we know that the edge is executed
200 on every invocation of the caller (i.e. its call statement dominates
201 exit block). We do not track this information, yet. */
202 stack_size_limit += ((gcov_type)stack_size_limit
203 * param_stack_frame_growth / 100);
205 inlined_stack = (ipa_get_stack_frame_offset (to)
206 + outer_info->estimated_self_stack_size
207 + what_info->estimated_stack_size);
208 /* Check new stack consumption with stack consumption at the place
209 stack is used. */
210 if (inlined_stack > stack_size_limit
211 /* If function already has large stack usage from sibling
212 inline call, we can inline, too.
213 This bit overoptimistically assume that we are good at stack
214 packing. */
215 && inlined_stack > ipa_fn_summaries->get (to)->estimated_stack_size
216 && inlined_stack > param_large_stack_frame)
218 e->inline_failed = CIF_LARGE_STACK_FRAME_GROWTH_LIMIT;
219 return false;
221 return true;
224 /* Dump info about why inlining has failed. */
226 static void
227 report_inline_failed_reason (struct cgraph_edge *e)
229 if (dump_enabled_p ())
231 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
232 " not inlinable: %C -> %C, %s\n",
233 e->caller, e->callee,
234 cgraph_inline_failed_string (e->inline_failed));
235 if ((e->inline_failed == CIF_TARGET_OPTION_MISMATCH
236 || e->inline_failed == CIF_OPTIMIZATION_MISMATCH)
237 && e->caller->lto_file_data
238 && e->callee->ultimate_alias_target ()->lto_file_data)
240 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
241 " LTO objects: %s, %s\n",
242 e->caller->lto_file_data->file_name,
243 e->callee->ultimate_alias_target ()->lto_file_data->file_name);
245 if (e->inline_failed == CIF_TARGET_OPTION_MISMATCH)
246 if (dump_file)
247 cl_target_option_print_diff
248 (dump_file, 2, target_opts_for_fn (e->caller->decl),
249 target_opts_for_fn (e->callee->ultimate_alias_target ()->decl));
250 if (e->inline_failed == CIF_OPTIMIZATION_MISMATCH)
251 if (dump_file)
252 cl_optimization_print_diff
253 (dump_file, 2, opts_for_fn (e->caller->decl),
254 opts_for_fn (e->callee->ultimate_alias_target ()->decl));
258 /* Decide whether sanitizer-related attributes allow inlining. */
260 static bool
261 sanitize_attrs_match_for_inline_p (const_tree caller, const_tree callee)
263 if (!caller || !callee)
264 return true;
266 /* Allow inlining always_inline functions into no_sanitize_address
267 functions. */
268 if (!sanitize_flags_p (SANITIZE_ADDRESS, caller)
269 && lookup_attribute ("always_inline", DECL_ATTRIBUTES (callee)))
270 return true;
272 return ((sanitize_flags_p (SANITIZE_ADDRESS, caller)
273 == sanitize_flags_p (SANITIZE_ADDRESS, callee))
274 && (sanitize_flags_p (SANITIZE_POINTER_COMPARE, caller)
275 == sanitize_flags_p (SANITIZE_POINTER_COMPARE, callee))
276 && (sanitize_flags_p (SANITIZE_POINTER_SUBTRACT, caller)
277 == sanitize_flags_p (SANITIZE_POINTER_SUBTRACT, callee)));
280 /* Used for flags where it is safe to inline when caller's value is
281 grater than callee's. */
282 #define check_maybe_up(flag) \
283 (opts_for_fn (caller->decl)->x_##flag \
284 != opts_for_fn (callee->decl)->x_##flag \
285 && (!always_inline \
286 || opts_for_fn (caller->decl)->x_##flag \
287 < opts_for_fn (callee->decl)->x_##flag))
288 /* Used for flags where it is safe to inline when caller's value is
289 smaller than callee's. */
290 #define check_maybe_down(flag) \
291 (opts_for_fn (caller->decl)->x_##flag \
292 != opts_for_fn (callee->decl)->x_##flag \
293 && (!always_inline \
294 || opts_for_fn (caller->decl)->x_##flag \
295 > opts_for_fn (callee->decl)->x_##flag))
296 /* Used for flags where exact match is needed for correctness. */
297 #define check_match(flag) \
298 (opts_for_fn (caller->decl)->x_##flag \
299 != opts_for_fn (callee->decl)->x_##flag)
301 /* Decide if we can inline the edge and possibly update
302 inline_failed reason.
303 We check whether inlining is possible at all and whether
304 caller growth limits allow doing so.
306 if REPORT is true, output reason to the dump file. */
308 static bool
309 can_inline_edge_p (struct cgraph_edge *e, bool report,
310 bool early = false)
312 gcc_checking_assert (e->inline_failed);
314 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
316 if (report)
317 report_inline_failed_reason (e);
318 return false;
321 bool inlinable = true;
322 enum availability avail;
323 cgraph_node *caller = (e->caller->inlined_to
324 ? e->caller->inlined_to : e->caller);
325 cgraph_node *callee = e->callee->ultimate_alias_target (&avail, caller);
327 if (!callee->definition)
329 e->inline_failed = CIF_BODY_NOT_AVAILABLE;
330 inlinable = false;
332 if (!early && (!opt_for_fn (callee->decl, optimize)
333 || !opt_for_fn (caller->decl, optimize)))
335 e->inline_failed = CIF_FUNCTION_NOT_OPTIMIZED;
336 inlinable = false;
338 else if (callee->calls_comdat_local)
340 e->inline_failed = CIF_USES_COMDAT_LOCAL;
341 inlinable = false;
343 else if (avail <= AVAIL_INTERPOSABLE)
345 e->inline_failed = CIF_OVERWRITABLE;
346 inlinable = false;
348 /* All edges with call_stmt_cannot_inline_p should have inline_failed
349 initialized to one of FINAL_ERROR reasons. */
350 else if (e->call_stmt_cannot_inline_p)
351 gcc_unreachable ();
352 /* Don't inline if the functions have different EH personalities. */
353 else if (DECL_FUNCTION_PERSONALITY (caller->decl)
354 && DECL_FUNCTION_PERSONALITY (callee->decl)
355 && (DECL_FUNCTION_PERSONALITY (caller->decl)
356 != DECL_FUNCTION_PERSONALITY (callee->decl)))
358 e->inline_failed = CIF_EH_PERSONALITY;
359 inlinable = false;
361 /* TM pure functions should not be inlined into non-TM_pure
362 functions. */
363 else if (is_tm_pure (callee->decl) && !is_tm_pure (caller->decl))
365 e->inline_failed = CIF_UNSPECIFIED;
366 inlinable = false;
368 /* Check compatibility of target optimization options. */
369 else if (!targetm.target_option.can_inline_p (caller->decl,
370 callee->decl))
372 e->inline_failed = CIF_TARGET_OPTION_MISMATCH;
373 inlinable = false;
375 else if (ipa_fn_summaries->get (callee) == NULL
376 || !ipa_fn_summaries->get (callee)->inlinable)
378 e->inline_failed = CIF_FUNCTION_NOT_INLINABLE;
379 inlinable = false;
381 /* Don't inline a function with mismatched sanitization attributes. */
382 else if (!sanitize_attrs_match_for_inline_p (caller->decl, callee->decl))
384 e->inline_failed = CIF_ATTRIBUTE_MISMATCH;
385 inlinable = false;
387 if (!inlinable && report)
388 report_inline_failed_reason (e);
389 return inlinable;
392 /* Return inlining_insns_single limit for function N. If HINT is true
393 scale up the bound. */
395 static int
396 inline_insns_single (cgraph_node *n, bool hint)
398 if (opt_for_fn (n->decl, optimize) >= 3)
400 if (hint)
401 return param_max_inline_insns_single
402 * param_inline_heuristics_hint_percent / 100;
403 return param_max_inline_insns_single;
405 else
407 if (hint)
408 return param_max_inline_insns_single_o2
409 * param_inline_heuristics_hint_percent_o2 / 100;
410 return param_max_inline_insns_single_o2;
414 /* Return inlining_insns_auto limit for function N. If HINT is true
415 scale up the bound. */
417 static int
418 inline_insns_auto (cgraph_node *n, bool hint)
420 int max_inline_insns_auto = opt_for_fn (n->decl, param_max_inline_insns_auto);
421 if (hint)
422 return max_inline_insns_auto * param_inline_heuristics_hint_percent / 100;
423 return max_inline_insns_auto;
426 /* Decide if we can inline the edge and possibly update
427 inline_failed reason.
428 We check whether inlining is possible at all and whether
429 caller growth limits allow doing so.
431 if REPORT is true, output reason to the dump file.
433 if DISREGARD_LIMITS is true, ignore size limits. */
435 static bool
436 can_inline_edge_by_limits_p (struct cgraph_edge *e, bool report,
437 bool disregard_limits = false, bool early = false)
439 gcc_checking_assert (e->inline_failed);
441 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
443 if (report)
444 report_inline_failed_reason (e);
445 return false;
448 bool inlinable = true;
449 enum availability avail;
450 cgraph_node *caller = (e->caller->inlined_to
451 ? e->caller->inlined_to : e->caller);
452 cgraph_node *callee = e->callee->ultimate_alias_target (&avail, caller);
453 tree caller_tree = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (caller->decl);
454 tree callee_tree
455 = callee ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (callee->decl) : NULL;
456 /* Check if caller growth allows the inlining. */
457 if (!DECL_DISREGARD_INLINE_LIMITS (callee->decl)
458 && !disregard_limits
459 && !lookup_attribute ("flatten",
460 DECL_ATTRIBUTES (caller->decl))
461 && !caller_growth_limits (e))
462 inlinable = false;
463 else if (callee->externally_visible
464 && !DECL_DISREGARD_INLINE_LIMITS (callee->decl)
465 && flag_live_patching == LIVE_PATCHING_INLINE_ONLY_STATIC)
467 e->inline_failed = CIF_EXTERN_LIVE_ONLY_STATIC;
468 inlinable = false;
470 /* Don't inline a function with a higher optimization level than the
471 caller. FIXME: this is really just tip of iceberg of handling
472 optimization attribute. */
473 else if (caller_tree != callee_tree)
475 bool always_inline =
476 (DECL_DISREGARD_INLINE_LIMITS (callee->decl)
477 && lookup_attribute ("always_inline",
478 DECL_ATTRIBUTES (callee->decl)));
479 ipa_fn_summary *caller_info = ipa_fn_summaries->get (caller);
480 ipa_fn_summary *callee_info = ipa_fn_summaries->get (callee);
482 /* Until GCC 4.9 we did not check the semantics-altering flags
483 below and inlined across optimization boundaries.
484 Enabling checks below breaks several packages by refusing
485 to inline library always_inline functions. See PR65873.
486 Disable the check for early inlining for now until better solution
487 is found. */
488 if (always_inline && early)
490 /* There are some options that change IL semantics which means
491 we cannot inline in these cases for correctness reason.
492 Not even for always_inline declared functions. */
493 else if (check_match (flag_wrapv)
494 || check_match (flag_trapv)
495 || check_match (flag_pcc_struct_return)
496 /* When caller or callee does FP math, be sure FP codegen flags
497 compatible. */
498 || ((caller_info->fp_expressions && callee_info->fp_expressions)
499 && (check_maybe_up (flag_rounding_math)
500 || check_maybe_up (flag_trapping_math)
501 || check_maybe_down (flag_unsafe_math_optimizations)
502 || check_maybe_down (flag_finite_math_only)
503 || check_maybe_up (flag_signaling_nans)
504 || check_maybe_down (flag_cx_limited_range)
505 || check_maybe_up (flag_signed_zeros)
506 || check_maybe_down (flag_associative_math)
507 || check_maybe_down (flag_reciprocal_math)
508 || check_maybe_down (flag_fp_int_builtin_inexact)
509 /* Strictly speaking only when the callee contains function
510 calls that may end up setting errno. */
511 || check_maybe_up (flag_errno_math)))
512 /* We do not want to make code compiled with exceptions to be
513 brought into a non-EH function unless we know that the callee
514 does not throw.
515 This is tracked by DECL_FUNCTION_PERSONALITY. */
516 || (check_maybe_up (flag_non_call_exceptions)
517 && DECL_FUNCTION_PERSONALITY (callee->decl))
518 || (check_maybe_up (flag_exceptions)
519 && DECL_FUNCTION_PERSONALITY (callee->decl))
520 /* When devirtualization is diabled for callee, it is not safe
521 to inline it as we possibly mangled the type info.
522 Allow early inlining of always inlines. */
523 || (!early && check_maybe_down (flag_devirtualize)))
525 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
526 inlinable = false;
528 /* gcc.dg/pr43564.c. Apply user-forced inline even at -O0. */
529 else if (always_inline)
531 /* When user added an attribute to the callee honor it. */
532 else if (lookup_attribute ("optimize", DECL_ATTRIBUTES (callee->decl))
533 && opts_for_fn (caller->decl) != opts_for_fn (callee->decl))
535 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
536 inlinable = false;
538 /* If explicit optimize attribute are not used, the mismatch is caused
539 by different command line options used to build different units.
540 Do not care about COMDAT functions - those are intended to be
541 optimized with the optimization flags of module they are used in.
542 Also do not care about mixing up size/speed optimization when
543 DECL_DISREGARD_INLINE_LIMITS is set. */
544 else if ((callee->merged_comdat
545 && !lookup_attribute ("optimize",
546 DECL_ATTRIBUTES (caller->decl)))
547 || DECL_DISREGARD_INLINE_LIMITS (callee->decl))
549 /* If mismatch is caused by merging two LTO units with different
550 optimizationflags we want to be bit nicer. However never inline
551 if one of functions is not optimized at all. */
552 else if (!opt_for_fn (callee->decl, optimize)
553 || !opt_for_fn (caller->decl, optimize))
555 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
556 inlinable = false;
558 /* If callee is optimized for size and caller is not, allow inlining if
559 code shrinks or we are in param_max_inline_insns_single limit and
560 callee is inline (and thus likely an unified comdat).
561 This will allow caller to run faster. */
562 else if (opt_for_fn (callee->decl, optimize_size)
563 > opt_for_fn (caller->decl, optimize_size))
565 int growth = estimate_edge_growth (e);
566 if (growth > param_max_inline_insns_size
567 && (!DECL_DECLARED_INLINE_P (callee->decl)
568 && growth >= MAX (inline_insns_single (caller, false),
569 inline_insns_auto (caller, false))))
571 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
572 inlinable = false;
575 /* If callee is more aggressively optimized for performance than caller,
576 we generally want to inline only cheap (runtime wise) functions. */
577 else if (opt_for_fn (callee->decl, optimize_size)
578 < opt_for_fn (caller->decl, optimize_size)
579 || (opt_for_fn (callee->decl, optimize)
580 > opt_for_fn (caller->decl, optimize)))
582 if (estimate_edge_time (e)
583 >= 20 + ipa_call_summaries->get (e)->call_stmt_time)
585 e->inline_failed = CIF_OPTIMIZATION_MISMATCH;
586 inlinable = false;
592 if (!inlinable && report)
593 report_inline_failed_reason (e);
594 return inlinable;
598 /* Return true if the edge E is inlinable during early inlining. */
600 static bool
601 can_early_inline_edge_p (struct cgraph_edge *e)
603 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
604 /* Early inliner might get called at WPA stage when IPA pass adds new
605 function. In this case we cannot really do any of early inlining
606 because function bodies are missing. */
607 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
608 return false;
609 if (!gimple_has_body_p (callee->decl))
611 e->inline_failed = CIF_BODY_NOT_AVAILABLE;
612 return false;
614 /* In early inliner some of callees may not be in SSA form yet
615 (i.e. the callgraph is cyclic and we did not process
616 the callee by early inliner, yet). We don't have CIF code for this
617 case; later we will re-do the decision in the real inliner. */
618 if (!gimple_in_ssa_p (DECL_STRUCT_FUNCTION (e->caller->decl))
619 || !gimple_in_ssa_p (DECL_STRUCT_FUNCTION (callee->decl)))
621 if (dump_enabled_p ())
622 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
623 " edge not inlinable: not in SSA form\n");
624 return false;
626 if (!can_inline_edge_p (e, true, true)
627 || !can_inline_edge_by_limits_p (e, true, false, true))
628 return false;
629 return true;
633 /* Return number of calls in N. Ignore cheap builtins. */
635 static int
636 num_calls (struct cgraph_node *n)
638 struct cgraph_edge *e;
639 int num = 0;
641 for (e = n->callees; e; e = e->next_callee)
642 if (!is_inexpensive_builtin (e->callee->decl))
643 num++;
644 return num;
648 /* Return true if we are interested in inlining small function. */
650 static bool
651 want_early_inline_function_p (struct cgraph_edge *e)
653 bool want_inline = true;
654 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
656 if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
658 /* For AutoFDO, we need to make sure that before profile summary, all
659 hot paths' IR look exactly the same as profiled binary. As a result,
660 in einliner, we will disregard size limit and inline those callsites
661 that are:
662 * inlined in the profiled binary, and
663 * the cloned callee has enough samples to be considered "hot". */
664 else if (flag_auto_profile && afdo_callsite_hot_enough_for_early_inline (e))
666 else if (!DECL_DECLARED_INLINE_P (callee->decl)
667 && !opt_for_fn (e->caller->decl, flag_inline_small_functions))
669 e->inline_failed = CIF_FUNCTION_NOT_INLINE_CANDIDATE;
670 report_inline_failed_reason (e);
671 want_inline = false;
673 else
675 int growth = estimate_edge_growth (e);
676 int n;
677 int early_inlining_insns = opt_for_fn (e->caller->decl, optimize) >= 3
678 ? param_early_inlining_insns
679 : param_early_inlining_insns_o2;
682 if (growth <= param_max_inline_insns_size)
684 else if (!e->maybe_hot_p ())
686 if (dump_enabled_p ())
687 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
688 " will not early inline: %C->%C, "
689 "call is cold and code would grow by %i\n",
690 e->caller, callee,
691 growth);
692 want_inline = false;
694 else if (growth > early_inlining_insns)
696 if (dump_enabled_p ())
697 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
698 " will not early inline: %C->%C, "
699 "growth %i exceeds --param early-inlining-insns%s\n",
700 e->caller, callee, growth,
701 opt_for_fn (e->caller->decl, optimize) >= 3
702 ? "" : "-O2");
703 want_inline = false;
705 else if ((n = num_calls (callee)) != 0
706 && growth * (n + 1) > early_inlining_insns)
708 if (dump_enabled_p ())
709 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
710 " will not early inline: %C->%C, "
711 "growth %i exceeds --param early-inlining-insns%s "
712 "divided by number of calls\n",
713 e->caller, callee, growth,
714 opt_for_fn (e->caller->decl, optimize) >= 3
715 ? "" : "-O2");
716 want_inline = false;
719 return want_inline;
722 /* Compute time of the edge->caller + edge->callee execution when inlining
723 does not happen. */
725 inline sreal
726 compute_uninlined_call_time (struct cgraph_edge *edge,
727 sreal uninlined_call_time,
728 sreal freq)
730 cgraph_node *caller = (edge->caller->inlined_to
731 ? edge->caller->inlined_to
732 : edge->caller);
734 if (freq > 0)
735 uninlined_call_time *= freq;
736 else
737 uninlined_call_time = uninlined_call_time >> 11;
739 sreal caller_time = ipa_fn_summaries->get (caller)->time;
740 return uninlined_call_time + caller_time;
743 /* Same as compute_uinlined_call_time but compute time when inlining
744 does happen. */
746 inline sreal
747 compute_inlined_call_time (struct cgraph_edge *edge,
748 sreal time,
749 sreal freq)
751 cgraph_node *caller = (edge->caller->inlined_to
752 ? edge->caller->inlined_to
753 : edge->caller);
754 sreal caller_time = ipa_fn_summaries->get (caller)->time;
756 if (freq > 0)
757 time *= freq;
758 else
759 time = time >> 11;
761 /* This calculation should match one in ipa-inline-analysis.c
762 (estimate_edge_size_and_time). */
763 time -= (sreal)ipa_call_summaries->get (edge)->call_stmt_time * freq;
764 time += caller_time;
765 if (time <= 0)
766 time = ((sreal) 1) >> 8;
767 gcc_checking_assert (time >= 0);
768 return time;
771 /* Return true if the speedup for inlining E is bigger than
772 PARAM_MAX_INLINE_MIN_SPEEDUP. */
774 static bool
775 big_speedup_p (struct cgraph_edge *e)
777 sreal unspec_time;
778 sreal spec_time = estimate_edge_time (e, &unspec_time);
779 sreal freq = e->sreal_frequency ();
780 sreal time = compute_uninlined_call_time (e, unspec_time, freq);
781 sreal inlined_time = compute_inlined_call_time (e, spec_time, freq);
782 cgraph_node *caller = (e->caller->inlined_to
783 ? e->caller->inlined_to
784 : e->caller);
785 int limit = opt_for_fn (caller->decl, optimize) >= 3
786 ? param_inline_min_speedup
787 : param_inline_min_speedup_o2;
789 if ((time - inlined_time) * 100 > time * limit)
790 return true;
791 return false;
794 /* Return true if we are interested in inlining small function.
795 When REPORT is true, report reason to dump file. */
797 static bool
798 want_inline_small_function_p (struct cgraph_edge *e, bool report)
800 bool want_inline = true;
801 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
803 /* Allow this function to be called before can_inline_edge_p,
804 since it's usually cheaper. */
805 if (cgraph_inline_failed_type (e->inline_failed) == CIF_FINAL_ERROR)
806 want_inline = false;
807 else if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
809 else if (!DECL_DECLARED_INLINE_P (callee->decl)
810 && !opt_for_fn (e->caller->decl, flag_inline_small_functions))
812 e->inline_failed = CIF_FUNCTION_NOT_INLINE_CANDIDATE;
813 want_inline = false;
815 /* Do fast and conservative check if the function can be good
816 inline candidate. */
817 else if ((!DECL_DECLARED_INLINE_P (callee->decl)
818 && (!e->count.ipa ().initialized_p () || !e->maybe_hot_p ()))
819 && ipa_fn_summaries->get (callee)->min_size
820 - ipa_call_summaries->get (e)->call_stmt_size
821 > inline_insns_auto (e->caller, true))
823 e->inline_failed = CIF_MAX_INLINE_INSNS_AUTO_LIMIT;
824 want_inline = false;
826 else if ((DECL_DECLARED_INLINE_P (callee->decl)
827 || e->count.ipa ().nonzero_p ())
828 && ipa_fn_summaries->get (callee)->min_size
829 - ipa_call_summaries->get (e)->call_stmt_size
830 > inline_insns_single (e->caller, true))
832 if (opt_for_fn (e->caller->decl, optimize) >= 3)
833 e->inline_failed = (DECL_DECLARED_INLINE_P (callee->decl)
834 ? CIF_MAX_INLINE_INSNS_SINGLE_LIMIT
835 : CIF_MAX_INLINE_INSNS_AUTO_LIMIT);
836 else
837 e->inline_failed = (DECL_DECLARED_INLINE_P (callee->decl)
838 ? CIF_MAX_INLINE_INSNS_SINGLE_O2_LIMIT
839 : CIF_MAX_INLINE_INSNS_AUTO_LIMIT);
840 want_inline = false;
842 else
844 int growth = estimate_edge_growth (e);
845 ipa_hints hints = estimate_edge_hints (e);
846 bool apply_hints = (hints & (INLINE_HINT_indirect_call
847 | INLINE_HINT_known_hot
848 | INLINE_HINT_loop_iterations
849 | INLINE_HINT_loop_stride));
851 if (growth <= param_max_inline_insns_size)
853 /* Apply param_max_inline_insns_single limit. Do not do so when
854 hints suggests that inlining given function is very profitable.
855 Avoid computation of big_speedup_p when not necessary to change
856 outcome of decision. */
857 else if (DECL_DECLARED_INLINE_P (callee->decl)
858 && growth >= inline_insns_single (e->caller, apply_hints)
859 && (apply_hints
860 || growth >= inline_insns_single (e->caller, true)
861 || !big_speedup_p (e)))
863 if (opt_for_fn (e->caller->decl, optimize) >= 3)
864 e->inline_failed = CIF_MAX_INLINE_INSNS_SINGLE_LIMIT;
865 else
866 e->inline_failed = CIF_MAX_INLINE_INSNS_SINGLE_O2_LIMIT;
867 want_inline = false;
869 else if (!DECL_DECLARED_INLINE_P (callee->decl)
870 && !opt_for_fn (e->caller->decl, flag_inline_functions)
871 && growth >= param_max_inline_insns_small)
873 /* growth_positive_p is expensive, always test it last. */
874 if (growth >= inline_insns_single (e->caller, false)
875 || growth_positive_p (callee, e, growth))
877 e->inline_failed = CIF_NOT_DECLARED_INLINED;
878 want_inline = false;
881 /* Apply param_max_inline_insns_auto limit for functions not declared
882 inline. Bypass the limit when speedup seems big. */
883 else if (!DECL_DECLARED_INLINE_P (callee->decl)
884 && growth >= inline_insns_auto (e->caller, apply_hints)
885 && (apply_hints
886 || growth >= inline_insns_auto (e->caller, true)
887 || !big_speedup_p (e)))
889 /* growth_positive_p is expensive, always test it last. */
890 if (growth >= inline_insns_single (e->caller, false)
891 || growth_positive_p (callee, e, growth))
893 e->inline_failed = CIF_MAX_INLINE_INSNS_AUTO_LIMIT;
894 want_inline = false;
897 /* If call is cold, do not inline when function body would grow. */
898 else if (!e->maybe_hot_p ()
899 && (growth >= inline_insns_single (e->caller, false)
900 || growth_positive_p (callee, e, growth)))
902 e->inline_failed = CIF_UNLIKELY_CALL;
903 want_inline = false;
906 if (!want_inline && report)
907 report_inline_failed_reason (e);
908 return want_inline;
911 /* EDGE is self recursive edge.
912 We hand two cases - when function A is inlining into itself
913 or when function A is being inlined into another inliner copy of function
914 A within function B.
916 In first case OUTER_NODE points to the toplevel copy of A, while
917 in the second case OUTER_NODE points to the outermost copy of A in B.
919 In both cases we want to be extra selective since
920 inlining the call will just introduce new recursive calls to appear. */
922 static bool
923 want_inline_self_recursive_call_p (struct cgraph_edge *edge,
924 struct cgraph_node *outer_node,
925 bool peeling,
926 int depth)
928 char const *reason = NULL;
929 bool want_inline = true;
930 sreal caller_freq = 1;
931 int max_depth = param_max_inline_recursive_depth_auto;
933 if (DECL_DECLARED_INLINE_P (edge->caller->decl))
934 max_depth = param_max_inline_recursive_depth;
936 if (!edge->maybe_hot_p ())
938 reason = "recursive call is cold";
939 want_inline = false;
941 else if (depth > max_depth)
943 reason = "--param max-inline-recursive-depth exceeded.";
944 want_inline = false;
946 else if (outer_node->inlined_to
947 && (caller_freq = outer_node->callers->sreal_frequency ()) == 0)
949 reason = "caller frequency is 0";
950 want_inline = false;
953 if (!want_inline)
955 /* Inlining of self recursive function into copy of itself within other
956 function is transformation similar to loop peeling.
958 Peeling is profitable if we can inline enough copies to make probability
959 of actual call to the self recursive function very small. Be sure that
960 the probability of recursion is small.
962 We ensure that the frequency of recursing is at most 1 - (1/max_depth).
963 This way the expected number of recursion is at most max_depth. */
964 else if (peeling)
966 sreal max_prob = (sreal)1 - ((sreal)1 / (sreal)max_depth);
967 int i;
968 for (i = 1; i < depth; i++)
969 max_prob = max_prob * max_prob;
970 if (edge->sreal_frequency () >= max_prob * caller_freq)
972 reason = "frequency of recursive call is too large";
973 want_inline = false;
976 /* Recursive inlining, i.e. equivalent of unrolling, is profitable if
977 recursion depth is large. We reduce function call overhead and increase
978 chances that things fit in hardware return predictor.
980 Recursive inlining might however increase cost of stack frame setup
981 actually slowing down functions whose recursion tree is wide rather than
982 deep.
984 Deciding reliably on when to do recursive inlining without profile feedback
985 is tricky. For now we disable recursive inlining when probability of self
986 recursion is low.
988 Recursive inlining of self recursive call within loop also results in
989 large loop depths that generally optimize badly. We may want to throttle
990 down inlining in those cases. In particular this seems to happen in one
991 of libstdc++ rb tree methods. */
992 else
994 if (edge->sreal_frequency () * 100
995 <= caller_freq
996 * param_min_inline_recursive_probability)
998 reason = "frequency of recursive call is too small";
999 want_inline = false;
1002 if (!want_inline && dump_enabled_p ())
1003 dump_printf_loc (MSG_MISSED_OPTIMIZATION, edge->call_stmt,
1004 " not inlining recursively: %s\n", reason);
1005 return want_inline;
1008 /* Return true when NODE has uninlinable caller;
1009 set HAS_HOT_CALL if it has hot call.
1010 Worker for cgraph_for_node_and_aliases. */
1012 static bool
1013 check_callers (struct cgraph_node *node, void *has_hot_call)
1015 struct cgraph_edge *e;
1016 for (e = node->callers; e; e = e->next_caller)
1018 if (!opt_for_fn (e->caller->decl, flag_inline_functions_called_once)
1019 || !opt_for_fn (e->caller->decl, optimize))
1020 return true;
1021 if (!can_inline_edge_p (e, true))
1022 return true;
1023 if (e->recursive_p ())
1024 return true;
1025 if (!can_inline_edge_by_limits_p (e, true))
1026 return true;
1027 if (!(*(bool *)has_hot_call) && e->maybe_hot_p ())
1028 *(bool *)has_hot_call = true;
1030 return false;
1033 /* If NODE has a caller, return true. */
1035 static bool
1036 has_caller_p (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED)
1038 if (node->callers)
1039 return true;
1040 return false;
1043 /* Decide if inlining NODE would reduce unit size by eliminating
1044 the offline copy of function.
1045 When COLD is true the cold calls are considered, too. */
1047 static bool
1048 want_inline_function_to_all_callers_p (struct cgraph_node *node, bool cold)
1050 bool has_hot_call = false;
1052 /* Aliases gets inlined along with the function they alias. */
1053 if (node->alias)
1054 return false;
1055 /* Already inlined? */
1056 if (node->inlined_to)
1057 return false;
1058 /* Does it have callers? */
1059 if (!node->call_for_symbol_and_aliases (has_caller_p, NULL, true))
1060 return false;
1061 /* Inlining into all callers would increase size? */
1062 if (growth_positive_p (node, NULL, INT_MIN) > 0)
1063 return false;
1064 /* All inlines must be possible. */
1065 if (node->call_for_symbol_and_aliases (check_callers, &has_hot_call,
1066 true))
1067 return false;
1068 if (!cold && !has_hot_call)
1069 return false;
1070 return true;
1073 /* A cost model driving the inlining heuristics in a way so the edges with
1074 smallest badness are inlined first. After each inlining is performed
1075 the costs of all caller edges of nodes affected are recomputed so the
1076 metrics may accurately depend on values such as number of inlinable callers
1077 of the function or function body size. */
1079 static sreal
1080 edge_badness (struct cgraph_edge *edge, bool dump)
1082 sreal badness;
1083 int growth;
1084 sreal edge_time, unspec_edge_time;
1085 struct cgraph_node *callee = edge->callee->ultimate_alias_target ();
1086 class ipa_fn_summary *callee_info = ipa_fn_summaries->get (callee);
1087 ipa_hints hints;
1088 cgraph_node *caller = (edge->caller->inlined_to
1089 ? edge->caller->inlined_to
1090 : edge->caller);
1092 growth = estimate_edge_growth (edge);
1093 edge_time = estimate_edge_time (edge, &unspec_edge_time);
1094 hints = estimate_edge_hints (edge);
1095 gcc_checking_assert (edge_time >= 0);
1096 /* Check that inlined time is better, but tolerate some roundoff issues.
1097 FIXME: When callee profile drops to 0 we account calls more. This
1098 should be fixed by never doing that. */
1099 gcc_checking_assert ((edge_time * 100
1100 - callee_info->time * 101).to_int () <= 0
1101 || callee->count.ipa ().initialized_p ());
1102 gcc_checking_assert (growth <= ipa_size_summaries->get (callee)->size);
1104 if (dump)
1106 fprintf (dump_file, " Badness calculation for %s -> %s\n",
1107 edge->caller->dump_name (),
1108 edge->callee->dump_name ());
1109 fprintf (dump_file, " size growth %i, time %f unspec %f ",
1110 growth,
1111 edge_time.to_double (),
1112 unspec_edge_time.to_double ());
1113 ipa_dump_hints (dump_file, hints);
1114 if (big_speedup_p (edge))
1115 fprintf (dump_file, " big_speedup");
1116 fprintf (dump_file, "\n");
1119 /* Always prefer inlining saving code size. */
1120 if (growth <= 0)
1122 badness = (sreal) (-SREAL_MIN_SIG + growth) << (SREAL_MAX_EXP / 256);
1123 if (dump)
1124 fprintf (dump_file, " %f: Growth %d <= 0\n", badness.to_double (),
1125 growth);
1127 /* Inlining into EXTERNAL functions is not going to change anything unless
1128 they are themselves inlined. */
1129 else if (DECL_EXTERNAL (caller->decl))
1131 if (dump)
1132 fprintf (dump_file, " max: function is external\n");
1133 return sreal::max ();
1135 /* When profile is available. Compute badness as:
1137 time_saved * caller_count
1138 goodness = -------------------------------------------------
1139 growth_of_caller * overall_growth * combined_size
1141 badness = - goodness
1143 Again use negative value to make calls with profile appear hotter
1144 then calls without.
1146 else if (opt_for_fn (caller->decl, flag_guess_branch_prob)
1147 || caller->count.ipa ().nonzero_p ())
1149 sreal numerator, denominator;
1150 int overall_growth;
1151 sreal freq = edge->sreal_frequency ();
1152 sreal inlined_time = compute_inlined_call_time (edge, edge_time, freq);
1154 numerator = (compute_uninlined_call_time (edge, unspec_edge_time, freq)
1155 - inlined_time);
1156 if (numerator <= 0)
1157 numerator = ((sreal) 1 >> 8);
1158 if (caller->count.ipa ().nonzero_p ())
1159 numerator *= caller->count.ipa ().to_gcov_type ();
1160 else if (caller->count.ipa ().initialized_p ())
1161 numerator = numerator >> 11;
1162 denominator = growth;
1164 overall_growth = callee_info->growth;
1166 /* Look for inliner wrappers of the form:
1168 inline_caller ()
1170 do_fast_job...
1171 if (need_more_work)
1172 noninline_callee ();
1174 Withhout penalizing this case, we usually inline noninline_callee
1175 into the inline_caller because overall_growth is small preventing
1176 further inlining of inline_caller.
1178 Penalize only callgraph edges to functions with small overall
1179 growth ...
1181 if (growth > overall_growth
1182 /* ... and having only one caller which is not inlined ... */
1183 && callee_info->single_caller
1184 && !edge->caller->inlined_to
1185 /* ... and edges executed only conditionally ... */
1186 && freq < 1
1187 /* ... consider case where callee is not inline but caller is ... */
1188 && ((!DECL_DECLARED_INLINE_P (edge->callee->decl)
1189 && DECL_DECLARED_INLINE_P (caller->decl))
1190 /* ... or when early optimizers decided to split and edge
1191 frequency still indicates splitting is a win ... */
1192 || (callee->split_part && !caller->split_part
1193 && freq * 100 < param_partial_inlining_entry_probability
1194 /* ... and do not overwrite user specified hints. */
1195 && (!DECL_DECLARED_INLINE_P (edge->callee->decl)
1196 || DECL_DECLARED_INLINE_P (caller->decl)))))
1198 ipa_fn_summary *caller_info = ipa_fn_summaries->get (caller);
1199 int caller_growth = caller_info->growth;
1201 /* Only apply the penalty when caller looks like inline candidate,
1202 and it is not called once. */
1203 if (!caller_info->single_caller && overall_growth < caller_growth
1204 && caller_info->inlinable
1205 && ipa_size_summaries->get (caller)->size
1206 < (DECL_DECLARED_INLINE_P (caller->decl)
1207 ? inline_insns_single (caller, false)
1208 : inline_insns_auto (caller, false)))
1210 if (dump)
1211 fprintf (dump_file,
1212 " Wrapper penalty. Increasing growth %i to %i\n",
1213 overall_growth, caller_growth);
1214 overall_growth = caller_growth;
1217 if (overall_growth > 0)
1219 /* Strongly preffer functions with few callers that can be inlined
1220 fully. The square root here leads to smaller binaries at average.
1221 Watch however for extreme cases and return to linear function
1222 when growth is large. */
1223 if (overall_growth < 256)
1224 overall_growth *= overall_growth;
1225 else
1226 overall_growth += 256 * 256 - 256;
1227 denominator *= overall_growth;
1229 denominator *= ipa_size_summaries->get (caller)->size + growth;
1231 badness = - numerator / denominator;
1233 if (dump)
1235 fprintf (dump_file,
1236 " %f: guessed profile. frequency %f, count %" PRId64
1237 " caller count %" PRId64
1238 " time w/o inlining %f, time with inlining %f"
1239 " overall growth %i (current) %i (original)"
1240 " %i (compensated)\n",
1241 badness.to_double (),
1242 freq.to_double (),
1243 edge->count.ipa ().initialized_p () ? edge->count.ipa ().to_gcov_type () : -1,
1244 caller->count.ipa ().initialized_p () ? caller->count.ipa ().to_gcov_type () : -1,
1245 compute_uninlined_call_time (edge,
1246 unspec_edge_time, freq).to_double (),
1247 inlined_time.to_double (),
1248 estimate_growth (callee),
1249 callee_info->growth, overall_growth);
1252 /* When function local profile is not available or it does not give
1253 useful information (ie frequency is zero), base the cost on
1254 loop nest and overall size growth, so we optimize for overall number
1255 of functions fully inlined in program. */
1256 else
1258 int nest = MIN (ipa_call_summaries->get (edge)->loop_depth, 8);
1259 badness = growth;
1261 /* Decrease badness if call is nested. */
1262 if (badness > 0)
1263 badness = badness >> nest;
1264 else
1265 badness = badness << nest;
1266 if (dump)
1267 fprintf (dump_file, " %f: no profile. nest %i\n",
1268 badness.to_double (), nest);
1270 gcc_checking_assert (badness != 0);
1272 if (edge->recursive_p ())
1273 badness = badness.shift (badness > 0 ? 4 : -4);
1274 if ((hints & (INLINE_HINT_indirect_call
1275 | INLINE_HINT_loop_iterations
1276 | INLINE_HINT_loop_stride))
1277 || callee_info->growth <= 0)
1278 badness = badness.shift (badness > 0 ? -2 : 2);
1279 if (hints & (INLINE_HINT_same_scc))
1280 badness = badness.shift (badness > 0 ? 3 : -3);
1281 else if (hints & (INLINE_HINT_in_scc))
1282 badness = badness.shift (badness > 0 ? 2 : -2);
1283 else if (hints & (INLINE_HINT_cross_module))
1284 badness = badness.shift (badness > 0 ? 1 : -1);
1285 if (DECL_DISREGARD_INLINE_LIMITS (callee->decl))
1286 badness = badness.shift (badness > 0 ? -4 : 4);
1287 else if ((hints & INLINE_HINT_declared_inline))
1288 badness = badness.shift (badness > 0 ? -3 : 3);
1289 if (dump)
1290 fprintf (dump_file, " Adjusted by hints %f\n", badness.to_double ());
1291 return badness;
1294 /* Recompute badness of EDGE and update its key in HEAP if needed. */
1295 static inline void
1296 update_edge_key (edge_heap_t *heap, struct cgraph_edge *edge)
1298 sreal badness = edge_badness (edge, false);
1299 if (edge->aux)
1301 edge_heap_node_t *n = (edge_heap_node_t *) edge->aux;
1302 gcc_checking_assert (n->get_data () == edge);
1304 /* fibonacci_heap::replace_key does busy updating of the
1305 heap that is unnecesarily expensive.
1306 We do lazy increases: after extracting minimum if the key
1307 turns out to be out of date, it is re-inserted into heap
1308 with correct value. */
1309 if (badness < n->get_key ())
1311 if (dump_file && (dump_flags & TDF_DETAILS))
1313 fprintf (dump_file,
1314 " decreasing badness %s -> %s, %f to %f\n",
1315 edge->caller->dump_name (),
1316 edge->callee->dump_name (),
1317 n->get_key ().to_double (),
1318 badness.to_double ());
1320 heap->decrease_key (n, badness);
1323 else
1325 if (dump_file && (dump_flags & TDF_DETAILS))
1327 fprintf (dump_file,
1328 " enqueuing call %s -> %s, badness %f\n",
1329 edge->caller->dump_name (),
1330 edge->callee->dump_name (),
1331 badness.to_double ());
1333 edge->aux = heap->insert (badness, edge);
1338 /* NODE was inlined.
1339 All caller edges needs to be resetted because
1340 size estimates change. Similarly callees needs reset
1341 because better context may be known. */
1343 static void
1344 reset_edge_caches (struct cgraph_node *node)
1346 struct cgraph_edge *edge;
1347 struct cgraph_edge *e = node->callees;
1348 struct cgraph_node *where = node;
1349 struct ipa_ref *ref;
1351 if (where->inlined_to)
1352 where = where->inlined_to;
1354 reset_node_cache (where);
1356 if (edge_growth_cache != NULL)
1357 for (edge = where->callers; edge; edge = edge->next_caller)
1358 if (edge->inline_failed)
1359 edge_growth_cache->remove (edge);
1361 FOR_EACH_ALIAS (where, ref)
1362 reset_edge_caches (dyn_cast <cgraph_node *> (ref->referring));
1364 if (!e)
1365 return;
1367 while (true)
1368 if (!e->inline_failed && e->callee->callees)
1369 e = e->callee->callees;
1370 else
1372 if (edge_growth_cache != NULL && e->inline_failed)
1373 edge_growth_cache->remove (e);
1374 if (e->next_callee)
1375 e = e->next_callee;
1376 else
1380 if (e->caller == node)
1381 return;
1382 e = e->caller->callers;
1384 while (!e->next_callee);
1385 e = e->next_callee;
1390 /* Recompute HEAP nodes for each of caller of NODE.
1391 UPDATED_NODES track nodes we already visited, to avoid redundant work.
1392 When CHECK_INLINABLITY_FOR is set, re-check for specified edge that
1393 it is inlinable. Otherwise check all edges. */
1395 static void
1396 update_caller_keys (edge_heap_t *heap, struct cgraph_node *node,
1397 bitmap updated_nodes,
1398 struct cgraph_edge *check_inlinablity_for)
1400 struct cgraph_edge *edge;
1401 struct ipa_ref *ref;
1403 if ((!node->alias && !ipa_fn_summaries->get (node)->inlinable)
1404 || node->inlined_to)
1405 return;
1406 if (!bitmap_set_bit (updated_nodes, node->get_uid ()))
1407 return;
1409 FOR_EACH_ALIAS (node, ref)
1411 struct cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
1412 update_caller_keys (heap, alias, updated_nodes, check_inlinablity_for);
1415 for (edge = node->callers; edge; edge = edge->next_caller)
1416 if (edge->inline_failed)
1418 if (!check_inlinablity_for
1419 || check_inlinablity_for == edge)
1421 if (can_inline_edge_p (edge, false)
1422 && want_inline_small_function_p (edge, false)
1423 && can_inline_edge_by_limits_p (edge, false))
1424 update_edge_key (heap, edge);
1425 else if (edge->aux)
1427 report_inline_failed_reason (edge);
1428 heap->delete_node ((edge_heap_node_t *) edge->aux);
1429 edge->aux = NULL;
1432 else if (edge->aux)
1433 update_edge_key (heap, edge);
1437 /* Recompute HEAP nodes for each uninlined call in NODE.
1438 This is used when we know that edge badnesses are going only to increase
1439 (we introduced new call site) and thus all we need is to insert newly
1440 created edges into heap. */
1442 static void
1443 update_callee_keys (edge_heap_t *heap, struct cgraph_node *node,
1444 bitmap updated_nodes)
1446 struct cgraph_edge *e = node->callees;
1448 if (!e)
1449 return;
1450 while (true)
1451 if (!e->inline_failed && e->callee->callees)
1452 e = e->callee->callees;
1453 else
1455 enum availability avail;
1456 struct cgraph_node *callee;
1457 /* We do not reset callee growth cache here. Since we added a new call,
1458 growth chould have just increased and consequentely badness metric
1459 don't need updating. */
1460 if (e->inline_failed
1461 && (callee = e->callee->ultimate_alias_target (&avail, e->caller))
1462 && ipa_fn_summaries->get (callee) != NULL
1463 && ipa_fn_summaries->get (callee)->inlinable
1464 && avail >= AVAIL_AVAILABLE
1465 && !bitmap_bit_p (updated_nodes, callee->get_uid ()))
1467 if (can_inline_edge_p (e, false)
1468 && want_inline_small_function_p (e, false)
1469 && can_inline_edge_by_limits_p (e, false))
1470 update_edge_key (heap, e);
1471 else if (e->aux)
1473 report_inline_failed_reason (e);
1474 heap->delete_node ((edge_heap_node_t *) e->aux);
1475 e->aux = NULL;
1478 if (e->next_callee)
1479 e = e->next_callee;
1480 else
1484 if (e->caller == node)
1485 return;
1486 e = e->caller->callers;
1488 while (!e->next_callee);
1489 e = e->next_callee;
1494 /* Enqueue all recursive calls from NODE into priority queue depending on
1495 how likely we want to recursively inline the call. */
1497 static void
1498 lookup_recursive_calls (struct cgraph_node *node, struct cgraph_node *where,
1499 edge_heap_t *heap)
1501 struct cgraph_edge *e;
1502 enum availability avail;
1504 for (e = where->callees; e; e = e->next_callee)
1505 if (e->callee == node
1506 || (e->callee->ultimate_alias_target (&avail, e->caller) == node
1507 && avail > AVAIL_INTERPOSABLE))
1508 heap->insert (-e->sreal_frequency (), e);
1509 for (e = where->callees; e; e = e->next_callee)
1510 if (!e->inline_failed)
1511 lookup_recursive_calls (node, e->callee, heap);
1514 /* Decide on recursive inlining: in the case function has recursive calls,
1515 inline until body size reaches given argument. If any new indirect edges
1516 are discovered in the process, add them to *NEW_EDGES, unless NEW_EDGES
1517 is NULL. */
1519 static bool
1520 recursive_inlining (struct cgraph_edge *edge,
1521 vec<cgraph_edge *> *new_edges)
1523 int limit = param_max_inline_insns_recursive_auto;
1524 edge_heap_t heap (sreal::min ());
1525 struct cgraph_node *node;
1526 struct cgraph_edge *e;
1527 struct cgraph_node *master_clone = NULL, *next;
1528 int depth = 0;
1529 int n = 0;
1531 node = edge->caller;
1532 if (node->inlined_to)
1533 node = node->inlined_to;
1535 if (DECL_DECLARED_INLINE_P (node->decl))
1536 limit = param_max_inline_insns_recursive;
1538 /* Make sure that function is small enough to be considered for inlining. */
1539 if (estimate_size_after_inlining (node, edge) >= limit)
1540 return false;
1541 lookup_recursive_calls (node, node, &heap);
1542 if (heap.empty ())
1543 return false;
1545 if (dump_file)
1546 fprintf (dump_file,
1547 " Performing recursive inlining on %s\n",
1548 node->name ());
1550 /* Do the inlining and update list of recursive call during process. */
1551 while (!heap.empty ())
1553 struct cgraph_edge *curr = heap.extract_min ();
1554 struct cgraph_node *cnode, *dest = curr->callee;
1556 if (!can_inline_edge_p (curr, true)
1557 || !can_inline_edge_by_limits_p (curr, true))
1558 continue;
1560 /* MASTER_CLONE is produced in the case we already started modified
1561 the function. Be sure to redirect edge to the original body before
1562 estimating growths otherwise we will be seeing growths after inlining
1563 the already modified body. */
1564 if (master_clone)
1566 curr->redirect_callee (master_clone);
1567 if (edge_growth_cache != NULL)
1568 edge_growth_cache->remove (curr);
1571 if (estimate_size_after_inlining (node, curr) > limit)
1573 curr->redirect_callee (dest);
1574 if (edge_growth_cache != NULL)
1575 edge_growth_cache->remove (curr);
1576 break;
1579 depth = 1;
1580 for (cnode = curr->caller;
1581 cnode->inlined_to; cnode = cnode->callers->caller)
1582 if (node->decl
1583 == curr->callee->ultimate_alias_target ()->decl)
1584 depth++;
1586 if (!want_inline_self_recursive_call_p (curr, node, false, depth))
1588 curr->redirect_callee (dest);
1589 if (edge_growth_cache != NULL)
1590 edge_growth_cache->remove (curr);
1591 continue;
1594 if (dump_file)
1596 fprintf (dump_file,
1597 " Inlining call of depth %i", depth);
1598 if (node->count.nonzero_p () && curr->count.initialized_p ())
1600 fprintf (dump_file, " called approx. %.2f times per call",
1601 (double)curr->count.to_gcov_type ()
1602 / node->count.to_gcov_type ());
1604 fprintf (dump_file, "\n");
1606 if (!master_clone)
1608 /* We need original clone to copy around. */
1609 master_clone = node->create_clone (node->decl, node->count,
1610 false, vNULL, true, NULL, NULL);
1611 for (e = master_clone->callees; e; e = e->next_callee)
1612 if (!e->inline_failed)
1613 clone_inlined_nodes (e, true, false, NULL);
1614 curr->redirect_callee (master_clone);
1615 if (edge_growth_cache != NULL)
1616 edge_growth_cache->remove (curr);
1619 inline_call (curr, false, new_edges, &overall_size, true);
1620 reset_node_cache (node);
1621 lookup_recursive_calls (node, curr->callee, &heap);
1622 n++;
1625 if (!heap.empty () && dump_file)
1626 fprintf (dump_file, " Recursive inlining growth limit met.\n");
1628 if (!master_clone)
1629 return false;
1631 if (dump_enabled_p ())
1632 dump_printf_loc (MSG_NOTE, edge->call_stmt,
1633 "\n Inlined %i times, "
1634 "body grown from size %i to %i, time %f to %f\n", n,
1635 ipa_size_summaries->get (master_clone)->size,
1636 ipa_size_summaries->get (node)->size,
1637 ipa_fn_summaries->get (master_clone)->time.to_double (),
1638 ipa_fn_summaries->get (node)->time.to_double ());
1640 /* Remove master clone we used for inlining. We rely that clones inlined
1641 into master clone gets queued just before master clone so we don't
1642 need recursion. */
1643 for (node = symtab->first_function (); node != master_clone;
1644 node = next)
1646 next = symtab->next_function (node);
1647 if (node->inlined_to == master_clone)
1648 node->remove ();
1650 master_clone->remove ();
1651 return true;
1655 /* Given whole compilation unit estimate of INSNS, compute how large we can
1656 allow the unit to grow. */
1658 static int
1659 compute_max_insns (int insns)
1661 int max_insns = insns;
1662 if (max_insns < param_large_unit_insns)
1663 max_insns = param_large_unit_insns;
1665 return ((int64_t) max_insns
1666 * (100 + param_inline_unit_growth) / 100);
1670 /* Compute badness of all edges in NEW_EDGES and add them to the HEAP. */
1672 static void
1673 add_new_edges_to_heap (edge_heap_t *heap, vec<cgraph_edge *> new_edges)
1675 while (new_edges.length () > 0)
1677 struct cgraph_edge *edge = new_edges.pop ();
1679 gcc_assert (!edge->aux);
1680 gcc_assert (edge->callee);
1681 if (edge->inline_failed
1682 && can_inline_edge_p (edge, true)
1683 && want_inline_small_function_p (edge, true)
1684 && can_inline_edge_by_limits_p (edge, true))
1685 edge->aux = heap->insert (edge_badness (edge, false), edge);
1689 /* Remove EDGE from the fibheap. */
1691 static void
1692 heap_edge_removal_hook (struct cgraph_edge *e, void *data)
1694 if (e->aux)
1696 ((edge_heap_t *)data)->delete_node ((edge_heap_node_t *)e->aux);
1697 e->aux = NULL;
1701 /* Return true if speculation of edge E seems useful.
1702 If ANTICIPATE_INLINING is true, be conservative and hope that E
1703 may get inlined. */
1705 bool
1706 speculation_useful_p (struct cgraph_edge *e, bool anticipate_inlining)
1708 /* If we have already decided to inline the edge, it seems useful. */
1709 if (!e->inline_failed)
1710 return true;
1712 enum availability avail;
1713 struct cgraph_node *target = e->callee->ultimate_alias_target (&avail,
1714 e->caller);
1715 struct cgraph_edge *direct, *indirect;
1716 struct ipa_ref *ref;
1718 gcc_assert (e->speculative && !e->indirect_unknown_callee);
1720 if (!e->maybe_hot_p ())
1721 return false;
1723 /* See if IP optimizations found something potentially useful about the
1724 function. For now we look only for CONST/PURE flags. Almost everything
1725 else we propagate is useless. */
1726 if (avail >= AVAIL_AVAILABLE)
1728 int ecf_flags = flags_from_decl_or_type (target->decl);
1729 if (ecf_flags & ECF_CONST)
1731 e->speculative_call_info (direct, indirect, ref);
1732 if (!(indirect->indirect_info->ecf_flags & ECF_CONST))
1733 return true;
1735 else if (ecf_flags & ECF_PURE)
1737 e->speculative_call_info (direct, indirect, ref);
1738 if (!(indirect->indirect_info->ecf_flags & ECF_PURE))
1739 return true;
1742 /* If we did not managed to inline the function nor redirect
1743 to an ipa-cp clone (that are seen by having local flag set),
1744 it is probably pointless to inline it unless hardware is missing
1745 indirect call predictor. */
1746 if (!anticipate_inlining && !target->local)
1747 return false;
1748 /* For overwritable targets there is not much to do. */
1749 if (!can_inline_edge_p (e, false)
1750 || !can_inline_edge_by_limits_p (e, false, true))
1751 return false;
1752 /* OK, speculation seems interesting. */
1753 return true;
1756 /* We know that EDGE is not going to be inlined.
1757 See if we can remove speculation. */
1759 static void
1760 resolve_noninline_speculation (edge_heap_t *edge_heap, struct cgraph_edge *edge)
1762 if (edge->speculative && !speculation_useful_p (edge, false))
1764 struct cgraph_node *node = edge->caller;
1765 struct cgraph_node *where = node->inlined_to
1766 ? node->inlined_to : node;
1767 auto_bitmap updated_nodes;
1769 if (edge->count.ipa ().initialized_p ())
1770 spec_rem += edge->count.ipa ();
1771 edge->resolve_speculation ();
1772 reset_edge_caches (where);
1773 ipa_update_overall_fn_summary (where);
1774 update_caller_keys (edge_heap, where,
1775 updated_nodes, NULL);
1776 update_callee_keys (edge_heap, where,
1777 updated_nodes);
1781 /* Return true if NODE should be accounted for overall size estimate.
1782 Skip all nodes optimized for size so we can measure the growth of hot
1783 part of program no matter of the padding. */
1785 bool
1786 inline_account_function_p (struct cgraph_node *node)
1788 return (!DECL_EXTERNAL (node->decl)
1789 && !opt_for_fn (node->decl, optimize_size)
1790 && node->frequency != NODE_FREQUENCY_UNLIKELY_EXECUTED);
1793 /* Count number of callers of NODE and store it into DATA (that
1794 points to int. Worker for cgraph_for_node_and_aliases. */
1796 static bool
1797 sum_callers (struct cgraph_node *node, void *data)
1799 struct cgraph_edge *e;
1800 int *num_calls = (int *)data;
1802 for (e = node->callers; e; e = e->next_caller)
1803 (*num_calls)++;
1804 return false;
1807 /* We only propagate across edges with non-interposable callee. */
1809 inline bool
1810 ignore_edge_p (struct cgraph_edge *e)
1812 enum availability avail;
1813 e->callee->function_or_virtual_thunk_symbol (&avail, e->caller);
1814 return (avail <= AVAIL_INTERPOSABLE);
1817 /* We use greedy algorithm for inlining of small functions:
1818 All inline candidates are put into prioritized heap ordered in
1819 increasing badness.
1821 The inlining of small functions is bounded by unit growth parameters. */
1823 static void
1824 inline_small_functions (void)
1826 struct cgraph_node *node;
1827 struct cgraph_edge *edge;
1828 edge_heap_t edge_heap (sreal::min ());
1829 auto_bitmap updated_nodes;
1830 int min_size, max_size;
1831 auto_vec<cgraph_edge *> new_indirect_edges;
1832 int initial_size = 0;
1833 struct cgraph_node **order = XCNEWVEC (cgraph_node *, symtab->cgraph_count);
1834 struct cgraph_edge_hook_list *edge_removal_hook_holder;
1835 new_indirect_edges.create (8);
1837 edge_removal_hook_holder
1838 = symtab->add_edge_removal_hook (&heap_edge_removal_hook, &edge_heap);
1840 /* Compute overall unit size and other global parameters used by badness
1841 metrics. */
1843 max_count = profile_count::uninitialized ();
1844 ipa_reduced_postorder (order, true, ignore_edge_p);
1845 free (order);
1847 FOR_EACH_DEFINED_FUNCTION (node)
1848 if (!node->inlined_to)
1850 if (!node->alias && node->analyzed
1851 && (node->has_gimple_body_p () || node->thunk.thunk_p)
1852 && opt_for_fn (node->decl, optimize))
1854 class ipa_fn_summary *info = ipa_fn_summaries->get (node);
1855 struct ipa_dfs_info *dfs = (struct ipa_dfs_info *) node->aux;
1857 /* Do not account external functions, they will be optimized out
1858 if not inlined. Also only count the non-cold portion of program. */
1859 if (inline_account_function_p (node))
1860 initial_size += ipa_size_summaries->get (node)->size;
1861 info->growth = estimate_growth (node);
1863 int num_calls = 0;
1864 node->call_for_symbol_and_aliases (sum_callers, &num_calls,
1865 true);
1866 if (num_calls == 1)
1867 info->single_caller = true;
1868 if (dfs && dfs->next_cycle)
1870 struct cgraph_node *n2;
1871 int id = dfs->scc_no + 1;
1872 for (n2 = node; n2;
1873 n2 = ((struct ipa_dfs_info *) n2->aux)->next_cycle)
1874 if (opt_for_fn (n2->decl, optimize))
1876 ipa_fn_summary *info2 = ipa_fn_summaries->get
1877 (n2->inlined_to ? n2->inlined_to : n2);
1878 if (info2->scc_no)
1879 break;
1880 info2->scc_no = id;
1885 for (edge = node->callers; edge; edge = edge->next_caller)
1886 max_count = max_count.max (edge->count.ipa ());
1888 ipa_free_postorder_info ();
1889 initialize_growth_caches ();
1891 if (dump_file)
1892 fprintf (dump_file,
1893 "\nDeciding on inlining of small functions. Starting with size %i.\n",
1894 initial_size);
1896 overall_size = initial_size;
1897 max_size = compute_max_insns (overall_size);
1898 min_size = overall_size;
1900 /* Populate the heap with all edges we might inline. */
1902 FOR_EACH_DEFINED_FUNCTION (node)
1904 bool update = false;
1905 struct cgraph_edge *next = NULL;
1906 bool has_speculative = false;
1908 if (!opt_for_fn (node->decl, optimize))
1909 continue;
1911 if (dump_file)
1912 fprintf (dump_file, "Enqueueing calls in %s.\n", node->dump_name ());
1914 for (edge = node->callees; edge; edge = next)
1916 next = edge->next_callee;
1917 if (edge->inline_failed
1918 && !edge->aux
1919 && can_inline_edge_p (edge, true)
1920 && want_inline_small_function_p (edge, true)
1921 && can_inline_edge_by_limits_p (edge, true)
1922 && edge->inline_failed)
1924 gcc_assert (!edge->aux);
1925 update_edge_key (&edge_heap, edge);
1927 if (edge->speculative)
1928 has_speculative = true;
1930 if (has_speculative)
1931 for (edge = node->callees; edge; edge = next)
1933 next = edge->next_callee;
1934 if (edge->speculative
1935 && !speculation_useful_p (edge, edge->aux != NULL))
1937 edge->resolve_speculation ();
1938 update = true;
1941 if (update)
1943 struct cgraph_node *where = node->inlined_to
1944 ? node->inlined_to : node;
1945 ipa_update_overall_fn_summary (where);
1946 reset_edge_caches (where);
1947 update_caller_keys (&edge_heap, where,
1948 updated_nodes, NULL);
1949 update_callee_keys (&edge_heap, where,
1950 updated_nodes);
1951 bitmap_clear (updated_nodes);
1955 gcc_assert (in_lto_p
1956 || !(max_count > 0)
1957 || (profile_info && flag_branch_probabilities));
1959 while (!edge_heap.empty ())
1961 int old_size = overall_size;
1962 struct cgraph_node *where, *callee;
1963 sreal badness = edge_heap.min_key ();
1964 sreal current_badness;
1965 int growth;
1967 edge = edge_heap.extract_min ();
1968 gcc_assert (edge->aux);
1969 edge->aux = NULL;
1970 if (!edge->inline_failed || !edge->callee->analyzed)
1971 continue;
1973 /* Be sure that caches are maintained consistent.
1974 This check is affected by scaling roundoff errors when compiling for
1975 IPA this we skip it in that case. */
1976 if (flag_checking && !edge->callee->count.ipa_p ()
1977 && (!max_count.initialized_p () || !max_count.nonzero_p ()))
1979 sreal cached_badness = edge_badness (edge, false);
1981 int old_size_est = estimate_edge_size (edge);
1982 sreal old_time_est = estimate_edge_time (edge);
1983 int old_hints_est = estimate_edge_hints (edge);
1985 if (edge_growth_cache != NULL)
1986 edge_growth_cache->remove (edge);
1987 reset_node_cache (edge->caller->inlined_to
1988 ? edge->caller->inlined_to
1989 : edge->caller);
1990 gcc_assert (old_size_est == estimate_edge_size (edge));
1991 gcc_assert (old_time_est == estimate_edge_time (edge));
1992 /* FIXME:
1994 gcc_assert (old_hints_est == estimate_edge_hints (edge));
1996 fails with profile feedback because some hints depends on
1997 maybe_hot_edge_p predicate and because callee gets inlined to other
1998 calls, the edge may become cold.
1999 This ought to be fixed by computing relative probabilities
2000 for given invocation but that will be better done once whole
2001 code is converted to sreals. Disable for now and revert to "wrong"
2002 value so enable/disable checking paths agree. */
2003 edge_growth_cache->get (edge)->hints = old_hints_est + 1;
2005 /* When updating the edge costs, we only decrease badness in the keys.
2006 Increases of badness are handled lazilly; when we see key with out
2007 of date value on it, we re-insert it now. */
2008 current_badness = edge_badness (edge, false);
2009 gcc_assert (cached_badness == current_badness);
2010 gcc_assert (current_badness >= badness);
2012 else
2013 current_badness = edge_badness (edge, false);
2014 if (current_badness != badness)
2016 if (edge_heap.min () && current_badness > edge_heap.min_key ())
2018 edge->aux = edge_heap.insert (current_badness, edge);
2019 continue;
2021 else
2022 badness = current_badness;
2025 if (!can_inline_edge_p (edge, true)
2026 || !can_inline_edge_by_limits_p (edge, true))
2028 resolve_noninline_speculation (&edge_heap, edge);
2029 continue;
2032 callee = edge->callee->ultimate_alias_target ();
2033 growth = estimate_edge_growth (edge);
2034 if (dump_file)
2036 fprintf (dump_file,
2037 "\nConsidering %s with %i size\n",
2038 callee->dump_name (),
2039 ipa_size_summaries->get (callee)->size);
2040 fprintf (dump_file,
2041 " to be inlined into %s in %s:%i\n"
2042 " Estimated badness is %f, frequency %.2f.\n",
2043 edge->caller->dump_name (),
2044 edge->call_stmt
2045 && (LOCATION_LOCUS (gimple_location ((const gimple *)
2046 edge->call_stmt))
2047 > BUILTINS_LOCATION)
2048 ? gimple_filename ((const gimple *) edge->call_stmt)
2049 : "unknown",
2050 edge->call_stmt
2051 ? gimple_lineno ((const gimple *) edge->call_stmt)
2052 : -1,
2053 badness.to_double (),
2054 edge->sreal_frequency ().to_double ());
2055 if (edge->count.ipa ().initialized_p ())
2057 fprintf (dump_file, " Called ");
2058 edge->count.ipa ().dump (dump_file);
2059 fprintf (dump_file, " times\n");
2061 if (dump_flags & TDF_DETAILS)
2062 edge_badness (edge, true);
2065 if (overall_size + growth > max_size
2066 && !DECL_DISREGARD_INLINE_LIMITS (callee->decl))
2068 edge->inline_failed = CIF_INLINE_UNIT_GROWTH_LIMIT;
2069 report_inline_failed_reason (edge);
2070 resolve_noninline_speculation (&edge_heap, edge);
2071 continue;
2074 if (!want_inline_small_function_p (edge, true))
2076 resolve_noninline_speculation (&edge_heap, edge);
2077 continue;
2080 /* Heuristics for inlining small functions work poorly for
2081 recursive calls where we do effects similar to loop unrolling.
2082 When inlining such edge seems profitable, leave decision on
2083 specific inliner. */
2084 if (edge->recursive_p ())
2086 where = edge->caller;
2087 if (where->inlined_to)
2088 where = where->inlined_to;
2089 if (!recursive_inlining (edge,
2090 opt_for_fn (edge->caller->decl,
2091 flag_indirect_inlining)
2092 ? &new_indirect_edges : NULL))
2094 edge->inline_failed = CIF_RECURSIVE_INLINING;
2095 resolve_noninline_speculation (&edge_heap, edge);
2096 continue;
2098 reset_edge_caches (where);
2099 /* Recursive inliner inlines all recursive calls of the function
2100 at once. Consequently we need to update all callee keys. */
2101 if (opt_for_fn (edge->caller->decl, flag_indirect_inlining))
2102 add_new_edges_to_heap (&edge_heap, new_indirect_edges);
2103 update_callee_keys (&edge_heap, where, updated_nodes);
2104 bitmap_clear (updated_nodes);
2106 else
2108 struct cgraph_node *outer_node = NULL;
2109 int depth = 0;
2111 /* Consider the case where self recursive function A is inlined
2112 into B. This is desired optimization in some cases, since it
2113 leads to effect similar of loop peeling and we might completely
2114 optimize out the recursive call. However we must be extra
2115 selective. */
2117 where = edge->caller;
2118 while (where->inlined_to)
2120 if (where->decl == callee->decl)
2121 outer_node = where, depth++;
2122 where = where->callers->caller;
2124 if (outer_node
2125 && !want_inline_self_recursive_call_p (edge, outer_node,
2126 true, depth))
2128 edge->inline_failed
2129 = (DECL_DISREGARD_INLINE_LIMITS (edge->callee->decl)
2130 ? CIF_RECURSIVE_INLINING : CIF_UNSPECIFIED);
2131 resolve_noninline_speculation (&edge_heap, edge);
2132 continue;
2134 else if (depth && dump_file)
2135 fprintf (dump_file, " Peeling recursion with depth %i\n", depth);
2137 gcc_checking_assert (!callee->inlined_to);
2138 inline_call (edge, true, &new_indirect_edges, &overall_size, true);
2139 add_new_edges_to_heap (&edge_heap, new_indirect_edges);
2141 reset_edge_caches (edge->callee);
2143 update_callee_keys (&edge_heap, where, updated_nodes);
2145 where = edge->caller;
2146 if (where->inlined_to)
2147 where = where->inlined_to;
2149 /* Our profitability metric can depend on local properties
2150 such as number of inlinable calls and size of the function body.
2151 After inlining these properties might change for the function we
2152 inlined into (since it's body size changed) and for the functions
2153 called by function we inlined (since number of it inlinable callers
2154 might change). */
2155 update_caller_keys (&edge_heap, where, updated_nodes, NULL);
2156 /* Offline copy count has possibly changed, recompute if profile is
2157 available. */
2158 struct cgraph_node *n = cgraph_node::get (edge->callee->decl);
2159 if (n != edge->callee && n->analyzed && n->count.ipa ().initialized_p ())
2160 update_callee_keys (&edge_heap, n, updated_nodes);
2161 bitmap_clear (updated_nodes);
2163 if (dump_enabled_p ())
2165 ipa_fn_summary *s = ipa_fn_summaries->get (where);
2167 /* dump_printf can't handle %+i. */
2168 char buf_net_change[100];
2169 snprintf (buf_net_change, sizeof buf_net_change, "%+i",
2170 overall_size - old_size);
2172 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, edge->call_stmt,
2173 " Inlined %C into %C which now has time %f and "
2174 "size %i, net change of %s.\n",
2175 edge->callee, edge->caller,
2176 s->time.to_double (),
2177 ipa_size_summaries->get (edge->caller)->size,
2178 buf_net_change);
2180 if (min_size > overall_size)
2182 min_size = overall_size;
2183 max_size = compute_max_insns (min_size);
2185 if (dump_file)
2186 fprintf (dump_file, "New minimal size reached: %i\n", min_size);
2190 free_growth_caches ();
2191 if (dump_enabled_p ())
2192 dump_printf (MSG_NOTE,
2193 "Unit growth for small function inlining: %i->%i (%i%%)\n",
2194 initial_size, overall_size,
2195 initial_size ? overall_size * 100 / (initial_size) - 100: 0);
2196 symtab->remove_edge_removal_hook (edge_removal_hook_holder);
2199 /* Flatten NODE. Performed both during early inlining and
2200 at IPA inlining time. */
2202 static void
2203 flatten_function (struct cgraph_node *node, bool early, bool update)
2205 struct cgraph_edge *e;
2207 /* We shouldn't be called recursively when we are being processed. */
2208 gcc_assert (node->aux == NULL);
2210 node->aux = (void *) node;
2212 for (e = node->callees; e; e = e->next_callee)
2214 struct cgraph_node *orig_callee;
2215 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
2217 /* We've hit cycle? It is time to give up. */
2218 if (callee->aux)
2220 if (dump_enabled_p ())
2221 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2222 "Not inlining %C into %C to avoid cycle.\n",
2223 callee, e->caller);
2224 if (cgraph_inline_failed_type (e->inline_failed) != CIF_FINAL_ERROR)
2225 e->inline_failed = CIF_RECURSIVE_INLINING;
2226 continue;
2229 /* When the edge is already inlined, we just need to recurse into
2230 it in order to fully flatten the leaves. */
2231 if (!e->inline_failed)
2233 flatten_function (callee, early, false);
2234 continue;
2237 /* Flatten attribute needs to be processed during late inlining. For
2238 extra code quality we however do flattening during early optimization,
2239 too. */
2240 if (!early
2241 ? !can_inline_edge_p (e, true)
2242 && !can_inline_edge_by_limits_p (e, true)
2243 : !can_early_inline_edge_p (e))
2244 continue;
2246 if (e->recursive_p ())
2248 if (dump_enabled_p ())
2249 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2250 "Not inlining: recursive call.\n");
2251 continue;
2254 if (gimple_in_ssa_p (DECL_STRUCT_FUNCTION (node->decl))
2255 != gimple_in_ssa_p (DECL_STRUCT_FUNCTION (callee->decl)))
2257 if (dump_enabled_p ())
2258 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2259 "Not inlining: SSA form does not match.\n");
2260 continue;
2263 /* Inline the edge and flatten the inline clone. Avoid
2264 recursing through the original node if the node was cloned. */
2265 if (dump_enabled_p ())
2266 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, e->call_stmt,
2267 " Inlining %C into %C.\n",
2268 callee, e->caller);
2269 orig_callee = callee;
2270 inline_call (e, true, NULL, NULL, false);
2271 if (e->callee != orig_callee)
2272 orig_callee->aux = (void *) node;
2273 flatten_function (e->callee, early, false);
2274 if (e->callee != orig_callee)
2275 orig_callee->aux = NULL;
2278 node->aux = NULL;
2279 cgraph_node *where = node->inlined_to ? node->inlined_to : node;
2280 if (update && opt_for_fn (where->decl, optimize))
2281 ipa_update_overall_fn_summary (where);
2284 /* Inline NODE to all callers. Worker for cgraph_for_node_and_aliases.
2285 DATA points to number of calls originally found so we avoid infinite
2286 recursion. */
2288 static bool
2289 inline_to_all_callers_1 (struct cgraph_node *node, void *data,
2290 hash_set<cgraph_node *> *callers)
2292 int *num_calls = (int *)data;
2293 bool callee_removed = false;
2295 while (node->callers && !node->inlined_to)
2297 struct cgraph_node *caller = node->callers->caller;
2299 if (!can_inline_edge_p (node->callers, true)
2300 || !can_inline_edge_by_limits_p (node->callers, true)
2301 || node->callers->recursive_p ())
2303 if (dump_file)
2304 fprintf (dump_file, "Uninlinable call found; giving up.\n");
2305 *num_calls = 0;
2306 return false;
2309 if (dump_file)
2311 cgraph_node *ultimate = node->ultimate_alias_target ();
2312 fprintf (dump_file,
2313 "\nInlining %s size %i.\n",
2314 ultimate->name (),
2315 ipa_size_summaries->get (ultimate)->size);
2316 fprintf (dump_file,
2317 " Called once from %s %i insns.\n",
2318 node->callers->caller->name (),
2319 ipa_size_summaries->get (node->callers->caller)->size);
2322 /* Remember which callers we inlined to, delaying updating the
2323 overall summary. */
2324 callers->add (node->callers->caller);
2325 inline_call (node->callers, true, NULL, NULL, false, &callee_removed);
2326 if (dump_file)
2327 fprintf (dump_file,
2328 " Inlined into %s which now has %i size\n",
2329 caller->name (),
2330 ipa_size_summaries->get (caller)->size);
2331 if (!(*num_calls)--)
2333 if (dump_file)
2334 fprintf (dump_file, "New calls found; giving up.\n");
2335 return callee_removed;
2337 if (callee_removed)
2338 return true;
2340 return false;
2343 /* Wrapper around inline_to_all_callers_1 doing delayed overall summary
2344 update. */
2346 static bool
2347 inline_to_all_callers (struct cgraph_node *node, void *data)
2349 hash_set<cgraph_node *> callers;
2350 bool res = inline_to_all_callers_1 (node, data, &callers);
2351 /* Perform the delayed update of the overall summary of all callers
2352 processed. This avoids quadratic behavior in the cases where
2353 we have a lot of calls to the same function. */
2354 for (hash_set<cgraph_node *>::iterator i = callers.begin ();
2355 i != callers.end (); ++i)
2356 ipa_update_overall_fn_summary ((*i)->inlined_to ? (*i)->inlined_to : *i);
2357 return res;
2360 /* Output overall time estimate. */
2361 static void
2362 dump_overall_stats (void)
2364 sreal sum_weighted = 0, sum = 0;
2365 struct cgraph_node *node;
2367 FOR_EACH_DEFINED_FUNCTION (node)
2368 if (!node->inlined_to
2369 && !node->alias)
2371 ipa_fn_summary *s = ipa_fn_summaries->get (node);
2372 if (s != NULL)
2374 sum += s->time;
2375 if (node->count.ipa ().initialized_p ())
2376 sum_weighted += s->time * node->count.ipa ().to_gcov_type ();
2379 fprintf (dump_file, "Overall time estimate: "
2380 "%f weighted by profile: "
2381 "%f\n", sum.to_double (), sum_weighted.to_double ());
2384 /* Output some useful stats about inlining. */
2386 static void
2387 dump_inline_stats (void)
2389 int64_t inlined_cnt = 0, inlined_indir_cnt = 0;
2390 int64_t inlined_virt_cnt = 0, inlined_virt_indir_cnt = 0;
2391 int64_t noninlined_cnt = 0, noninlined_indir_cnt = 0;
2392 int64_t noninlined_virt_cnt = 0, noninlined_virt_indir_cnt = 0;
2393 int64_t inlined_speculative = 0, inlined_speculative_ply = 0;
2394 int64_t indirect_poly_cnt = 0, indirect_cnt = 0;
2395 int64_t reason[CIF_N_REASONS][2];
2396 sreal reason_freq[CIF_N_REASONS];
2397 int i;
2398 struct cgraph_node *node;
2400 memset (reason, 0, sizeof (reason));
2401 for (i=0; i < CIF_N_REASONS; i++)
2402 reason_freq[i] = 0;
2403 FOR_EACH_DEFINED_FUNCTION (node)
2405 struct cgraph_edge *e;
2406 for (e = node->callees; e; e = e->next_callee)
2408 if (e->inline_failed)
2410 if (e->count.ipa ().initialized_p ())
2411 reason[(int) e->inline_failed][0] += e->count.ipa ().to_gcov_type ();
2412 reason_freq[(int) e->inline_failed] += e->sreal_frequency ();
2413 reason[(int) e->inline_failed][1] ++;
2414 if (DECL_VIRTUAL_P (e->callee->decl)
2415 && e->count.ipa ().initialized_p ())
2417 if (e->indirect_inlining_edge)
2418 noninlined_virt_indir_cnt += e->count.ipa ().to_gcov_type ();
2419 else
2420 noninlined_virt_cnt += e->count.ipa ().to_gcov_type ();
2422 else if (e->count.ipa ().initialized_p ())
2424 if (e->indirect_inlining_edge)
2425 noninlined_indir_cnt += e->count.ipa ().to_gcov_type ();
2426 else
2427 noninlined_cnt += e->count.ipa ().to_gcov_type ();
2430 else if (e->count.ipa ().initialized_p ())
2432 if (e->speculative)
2434 if (DECL_VIRTUAL_P (e->callee->decl))
2435 inlined_speculative_ply += e->count.ipa ().to_gcov_type ();
2436 else
2437 inlined_speculative += e->count.ipa ().to_gcov_type ();
2439 else if (DECL_VIRTUAL_P (e->callee->decl))
2441 if (e->indirect_inlining_edge)
2442 inlined_virt_indir_cnt += e->count.ipa ().to_gcov_type ();
2443 else
2444 inlined_virt_cnt += e->count.ipa ().to_gcov_type ();
2446 else
2448 if (e->indirect_inlining_edge)
2449 inlined_indir_cnt += e->count.ipa ().to_gcov_type ();
2450 else
2451 inlined_cnt += e->count.ipa ().to_gcov_type ();
2455 for (e = node->indirect_calls; e; e = e->next_callee)
2456 if (e->indirect_info->polymorphic
2457 & e->count.ipa ().initialized_p ())
2458 indirect_poly_cnt += e->count.ipa ().to_gcov_type ();
2459 else if (e->count.ipa ().initialized_p ())
2460 indirect_cnt += e->count.ipa ().to_gcov_type ();
2462 if (max_count.initialized_p ())
2464 fprintf (dump_file,
2465 "Inlined %" PRId64 " + speculative "
2466 "%" PRId64 " + speculative polymorphic "
2467 "%" PRId64 " + previously indirect "
2468 "%" PRId64 " + virtual "
2469 "%" PRId64 " + virtual and previously indirect "
2470 "%" PRId64 "\n" "Not inlined "
2471 "%" PRId64 " + previously indirect "
2472 "%" PRId64 " + virtual "
2473 "%" PRId64 " + virtual and previously indirect "
2474 "%" PRId64 " + stil indirect "
2475 "%" PRId64 " + still indirect polymorphic "
2476 "%" PRId64 "\n", inlined_cnt,
2477 inlined_speculative, inlined_speculative_ply,
2478 inlined_indir_cnt, inlined_virt_cnt, inlined_virt_indir_cnt,
2479 noninlined_cnt, noninlined_indir_cnt, noninlined_virt_cnt,
2480 noninlined_virt_indir_cnt, indirect_cnt, indirect_poly_cnt);
2481 fprintf (dump_file, "Removed speculations ");
2482 spec_rem.dump (dump_file);
2483 fprintf (dump_file, "\n");
2485 dump_overall_stats ();
2486 fprintf (dump_file, "\nWhy inlining failed?\n");
2487 for (i = 0; i < CIF_N_REASONS; i++)
2488 if (reason[i][1])
2489 fprintf (dump_file, "%-50s: %8i calls, %8f freq, %" PRId64" count\n",
2490 cgraph_inline_failed_string ((cgraph_inline_failed_t) i),
2491 (int) reason[i][1], reason_freq[i].to_double (), reason[i][0]);
2494 /* Called when node is removed. */
2496 static void
2497 flatten_remove_node_hook (struct cgraph_node *node, void *data)
2499 if (lookup_attribute ("flatten", DECL_ATTRIBUTES (node->decl)) == NULL)
2500 return;
2502 hash_set<struct cgraph_node *> *removed
2503 = (hash_set<struct cgraph_node *> *) data;
2504 removed->add (node);
2507 /* Decide on the inlining. We do so in the topological order to avoid
2508 expenses on updating data structures. */
2510 static unsigned int
2511 ipa_inline (void)
2513 struct cgraph_node *node;
2514 int nnodes;
2515 struct cgraph_node **order;
2516 int i, j;
2517 int cold;
2518 bool remove_functions = false;
2520 order = XCNEWVEC (struct cgraph_node *, symtab->cgraph_count);
2522 if (dump_file)
2523 ipa_dump_fn_summaries (dump_file);
2525 nnodes = ipa_reverse_postorder (order);
2526 spec_rem = profile_count::zero ();
2528 FOR_EACH_FUNCTION (node)
2530 node->aux = 0;
2532 /* Recompute the default reasons for inlining because they may have
2533 changed during merging. */
2534 if (in_lto_p)
2536 for (cgraph_edge *e = node->callees; e; e = e->next_callee)
2538 gcc_assert (e->inline_failed);
2539 initialize_inline_failed (e);
2541 for (cgraph_edge *e = node->indirect_calls; e; e = e->next_callee)
2542 initialize_inline_failed (e);
2546 if (dump_file)
2547 fprintf (dump_file, "\nFlattening functions:\n");
2549 /* First shrink order array, so that it only contains nodes with
2550 flatten attribute. */
2551 for (i = nnodes - 1, j = i; i >= 0; i--)
2553 node = order[i];
2554 if (node->definition
2555 && lookup_attribute ("flatten",
2556 DECL_ATTRIBUTES (node->decl)) != NULL)
2557 order[j--] = order[i];
2560 /* After the above loop, order[j + 1] ... order[nnodes - 1] contain
2561 nodes with flatten attribute. If there is more than one such
2562 node, we need to register a node removal hook, as flatten_function
2563 could remove other nodes with flatten attribute. See PR82801. */
2564 struct cgraph_node_hook_list *node_removal_hook_holder = NULL;
2565 hash_set<struct cgraph_node *> *flatten_removed_nodes = NULL;
2566 if (j < nnodes - 2)
2568 flatten_removed_nodes = new hash_set<struct cgraph_node *>;
2569 node_removal_hook_holder
2570 = symtab->add_cgraph_removal_hook (&flatten_remove_node_hook,
2571 flatten_removed_nodes);
2574 /* In the first pass handle functions to be flattened. Do this with
2575 a priority so none of our later choices will make this impossible. */
2576 for (i = nnodes - 1; i > j; i--)
2578 node = order[i];
2579 if (flatten_removed_nodes
2580 && flatten_removed_nodes->contains (node))
2581 continue;
2583 /* Handle nodes to be flattened.
2584 Ideally when processing callees we stop inlining at the
2585 entry of cycles, possibly cloning that entry point and
2586 try to flatten itself turning it into a self-recursive
2587 function. */
2588 if (dump_file)
2589 fprintf (dump_file, "Flattening %s\n", node->name ());
2590 flatten_function (node, false, true);
2593 if (j < nnodes - 2)
2595 symtab->remove_cgraph_removal_hook (node_removal_hook_holder);
2596 delete flatten_removed_nodes;
2598 free (order);
2600 if (dump_file)
2601 dump_overall_stats ();
2603 inline_small_functions ();
2605 gcc_assert (symtab->state == IPA_SSA);
2606 symtab->state = IPA_SSA_AFTER_INLINING;
2607 /* Do first after-inlining removal. We want to remove all "stale" extern
2608 inline functions and virtual functions so we really know what is called
2609 once. */
2610 symtab->remove_unreachable_nodes (dump_file);
2612 /* Inline functions with a property that after inlining into all callers the
2613 code size will shrink because the out-of-line copy is eliminated.
2614 We do this regardless on the callee size as long as function growth limits
2615 are met. */
2616 if (dump_file)
2617 fprintf (dump_file,
2618 "\nDeciding on functions to be inlined into all callers and "
2619 "removing useless speculations:\n");
2621 /* Inlining one function called once has good chance of preventing
2622 inlining other function into the same callee. Ideally we should
2623 work in priority order, but probably inlining hot functions first
2624 is good cut without the extra pain of maintaining the queue.
2626 ??? this is not really fitting the bill perfectly: inlining function
2627 into callee often leads to better optimization of callee due to
2628 increased context for optimization.
2629 For example if main() function calls a function that outputs help
2630 and then function that does the main optmization, we should inline
2631 the second with priority even if both calls are cold by themselves.
2633 We probably want to implement new predicate replacing our use of
2634 maybe_hot_edge interpreted as maybe_hot_edge || callee is known
2635 to be hot. */
2636 for (cold = 0; cold <= 1; cold ++)
2638 FOR_EACH_DEFINED_FUNCTION (node)
2640 struct cgraph_edge *edge, *next;
2641 bool update=false;
2643 if (!opt_for_fn (node->decl, optimize)
2644 || !opt_for_fn (node->decl, flag_inline_functions_called_once))
2645 continue;
2647 for (edge = node->callees; edge; edge = next)
2649 next = edge->next_callee;
2650 if (edge->speculative && !speculation_useful_p (edge, false))
2652 if (edge->count.ipa ().initialized_p ())
2653 spec_rem += edge->count.ipa ();
2654 edge->resolve_speculation ();
2655 update = true;
2656 remove_functions = true;
2659 if (update)
2661 struct cgraph_node *where = node->inlined_to
2662 ? node->inlined_to : node;
2663 reset_edge_caches (where);
2664 ipa_update_overall_fn_summary (where);
2666 if (want_inline_function_to_all_callers_p (node, cold))
2668 int num_calls = 0;
2669 node->call_for_symbol_and_aliases (sum_callers, &num_calls,
2670 true);
2671 while (node->call_for_symbol_and_aliases
2672 (inline_to_all_callers, &num_calls, true))
2674 remove_functions = true;
2679 /* Free ipa-prop structures if they are no longer needed. */
2680 ipa_free_all_structures_after_iinln ();
2682 if (dump_enabled_p ())
2683 dump_printf (MSG_NOTE,
2684 "\nInlined %i calls, eliminated %i functions\n\n",
2685 ncalls_inlined, nfunctions_inlined);
2686 if (dump_file)
2687 dump_inline_stats ();
2689 if (dump_file)
2690 ipa_dump_fn_summaries (dump_file);
2691 return remove_functions ? TODO_remove_functions : 0;
2694 /* Inline always-inline function calls in NODE. */
2696 static bool
2697 inline_always_inline_functions (struct cgraph_node *node)
2699 struct cgraph_edge *e;
2700 bool inlined = false;
2702 for (e = node->callees; e; e = e->next_callee)
2704 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
2705 if (!DECL_DISREGARD_INLINE_LIMITS (callee->decl))
2706 continue;
2708 if (e->recursive_p ())
2710 if (dump_enabled_p ())
2711 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2712 " Not inlining recursive call to %C.\n",
2713 e->callee);
2714 e->inline_failed = CIF_RECURSIVE_INLINING;
2715 continue;
2718 if (!can_early_inline_edge_p (e))
2720 /* Set inlined to true if the callee is marked "always_inline" but
2721 is not inlinable. This will allow flagging an error later in
2722 expand_call_inline in tree-inline.c. */
2723 if (lookup_attribute ("always_inline",
2724 DECL_ATTRIBUTES (callee->decl)) != NULL)
2725 inlined = true;
2726 continue;
2729 if (dump_enabled_p ())
2730 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, e->call_stmt,
2731 " Inlining %C into %C (always_inline).\n",
2732 e->callee, e->caller);
2733 inline_call (e, true, NULL, NULL, false);
2734 inlined = true;
2736 if (inlined)
2737 ipa_update_overall_fn_summary (node);
2739 return inlined;
2742 /* Decide on the inlining. We do so in the topological order to avoid
2743 expenses on updating data structures. */
2745 static bool
2746 early_inline_small_functions (struct cgraph_node *node)
2748 struct cgraph_edge *e;
2749 bool inlined = false;
2751 for (e = node->callees; e; e = e->next_callee)
2753 struct cgraph_node *callee = e->callee->ultimate_alias_target ();
2755 /* We can enounter not-yet-analyzed function during
2756 early inlining on callgraphs with strongly
2757 connected components. */
2758 ipa_fn_summary *s = ipa_fn_summaries->get (callee);
2759 if (s == NULL || !s->inlinable || !e->inline_failed)
2760 continue;
2762 /* Do not consider functions not declared inline. */
2763 if (!DECL_DECLARED_INLINE_P (callee->decl)
2764 && !opt_for_fn (node->decl, flag_inline_small_functions)
2765 && !opt_for_fn (node->decl, flag_inline_functions))
2766 continue;
2768 if (dump_enabled_p ())
2769 dump_printf_loc (MSG_NOTE, e->call_stmt,
2770 "Considering inline candidate %C.\n",
2771 callee);
2773 if (!can_early_inline_edge_p (e))
2774 continue;
2776 if (e->recursive_p ())
2778 if (dump_enabled_p ())
2779 dump_printf_loc (MSG_MISSED_OPTIMIZATION, e->call_stmt,
2780 " Not inlining: recursive call.\n");
2781 continue;
2784 if (!want_early_inline_function_p (e))
2785 continue;
2787 if (dump_enabled_p ())
2788 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, e->call_stmt,
2789 " Inlining %C into %C.\n",
2790 callee, e->caller);
2791 inline_call (e, true, NULL, NULL, false);
2792 inlined = true;
2795 if (inlined)
2796 ipa_update_overall_fn_summary (node);
2798 return inlined;
2801 unsigned int
2802 early_inliner (function *fun)
2804 struct cgraph_node *node = cgraph_node::get (current_function_decl);
2805 struct cgraph_edge *edge;
2806 unsigned int todo = 0;
2807 int iterations = 0;
2808 bool inlined = false;
2810 if (seen_error ())
2811 return 0;
2813 /* Do nothing if datastructures for ipa-inliner are already computed. This
2814 happens when some pass decides to construct new function and
2815 cgraph_add_new_function calls lowering passes and early optimization on
2816 it. This may confuse ourself when early inliner decide to inline call to
2817 function clone, because function clones don't have parameter list in
2818 ipa-prop matching their signature. */
2819 if (ipa_node_params_sum)
2820 return 0;
2822 if (flag_checking)
2823 node->verify ();
2824 node->remove_all_references ();
2826 /* Even when not optimizing or not inlining inline always-inline
2827 functions. */
2828 inlined = inline_always_inline_functions (node);
2830 if (!optimize
2831 || flag_no_inline
2832 || !flag_early_inlining
2833 /* Never inline regular functions into always-inline functions
2834 during incremental inlining. This sucks as functions calling
2835 always inline functions will get less optimized, but at the
2836 same time inlining of functions calling always inline
2837 function into an always inline function might introduce
2838 cycles of edges to be always inlined in the callgraph.
2840 We might want to be smarter and just avoid this type of inlining. */
2841 || (DECL_DISREGARD_INLINE_LIMITS (node->decl)
2842 && lookup_attribute ("always_inline",
2843 DECL_ATTRIBUTES (node->decl))))
2845 else if (lookup_attribute ("flatten",
2846 DECL_ATTRIBUTES (node->decl)) != NULL)
2848 /* When the function is marked to be flattened, recursively inline
2849 all calls in it. */
2850 if (dump_enabled_p ())
2851 dump_printf (MSG_OPTIMIZED_LOCATIONS,
2852 "Flattening %C\n", node);
2853 flatten_function (node, true, true);
2854 inlined = true;
2856 else
2858 /* If some always_inline functions was inlined, apply the changes.
2859 This way we will not account always inline into growth limits and
2860 moreover we will inline calls from always inlines that we skipped
2861 previously because of conditional above. */
2862 if (inlined)
2864 timevar_push (TV_INTEGRATION);
2865 todo |= optimize_inline_calls (current_function_decl);
2866 /* optimize_inline_calls call above might have introduced new
2867 statements that don't have inline parameters computed. */
2868 for (edge = node->callees; edge; edge = edge->next_callee)
2870 /* We can enounter not-yet-analyzed function during
2871 early inlining on callgraphs with strongly
2872 connected components. */
2873 ipa_call_summary *es = ipa_call_summaries->get_create (edge);
2874 es->call_stmt_size
2875 = estimate_num_insns (edge->call_stmt, &eni_size_weights);
2876 es->call_stmt_time
2877 = estimate_num_insns (edge->call_stmt, &eni_time_weights);
2879 ipa_update_overall_fn_summary (node);
2880 inlined = false;
2881 timevar_pop (TV_INTEGRATION);
2883 /* We iterate incremental inlining to get trivial cases of indirect
2884 inlining. */
2885 while (iterations < param_early_inliner_max_iterations
2886 && early_inline_small_functions (node))
2888 timevar_push (TV_INTEGRATION);
2889 todo |= optimize_inline_calls (current_function_decl);
2891 /* Technically we ought to recompute inline parameters so the new
2892 iteration of early inliner works as expected. We however have
2893 values approximately right and thus we only need to update edge
2894 info that might be cleared out for newly discovered edges. */
2895 for (edge = node->callees; edge; edge = edge->next_callee)
2897 /* We have no summary for new bound store calls yet. */
2898 ipa_call_summary *es = ipa_call_summaries->get_create (edge);
2899 es->call_stmt_size
2900 = estimate_num_insns (edge->call_stmt, &eni_size_weights);
2901 es->call_stmt_time
2902 = estimate_num_insns (edge->call_stmt, &eni_time_weights);
2904 if (iterations < param_early_inliner_max_iterations - 1)
2905 ipa_update_overall_fn_summary (node);
2906 timevar_pop (TV_INTEGRATION);
2907 iterations++;
2908 inlined = false;
2910 if (dump_file)
2911 fprintf (dump_file, "Iterations: %i\n", iterations);
2914 if (inlined)
2916 timevar_push (TV_INTEGRATION);
2917 todo |= optimize_inline_calls (current_function_decl);
2918 timevar_pop (TV_INTEGRATION);
2921 fun->always_inline_functions_inlined = true;
2923 return todo;
2926 /* Do inlining of small functions. Doing so early helps profiling and other
2927 passes to be somewhat more effective and avoids some code duplication in
2928 later real inlining pass for testcases with very many function calls. */
2930 namespace {
2932 const pass_data pass_data_early_inline =
2934 GIMPLE_PASS, /* type */
2935 "einline", /* name */
2936 OPTGROUP_INLINE, /* optinfo_flags */
2937 TV_EARLY_INLINING, /* tv_id */
2938 PROP_ssa, /* properties_required */
2939 0, /* properties_provided */
2940 0, /* properties_destroyed */
2941 0, /* todo_flags_start */
2942 0, /* todo_flags_finish */
2945 class pass_early_inline : public gimple_opt_pass
2947 public:
2948 pass_early_inline (gcc::context *ctxt)
2949 : gimple_opt_pass (pass_data_early_inline, ctxt)
2952 /* opt_pass methods: */
2953 virtual unsigned int execute (function *);
2955 }; // class pass_early_inline
2957 unsigned int
2958 pass_early_inline::execute (function *fun)
2960 return early_inliner (fun);
2963 } // anon namespace
2965 gimple_opt_pass *
2966 make_pass_early_inline (gcc::context *ctxt)
2968 return new pass_early_inline (ctxt);
2971 namespace {
2973 const pass_data pass_data_ipa_inline =
2975 IPA_PASS, /* type */
2976 "inline", /* name */
2977 OPTGROUP_INLINE, /* optinfo_flags */
2978 TV_IPA_INLINING, /* tv_id */
2979 0, /* properties_required */
2980 0, /* properties_provided */
2981 0, /* properties_destroyed */
2982 0, /* todo_flags_start */
2983 ( TODO_dump_symtab ), /* todo_flags_finish */
2986 class pass_ipa_inline : public ipa_opt_pass_d
2988 public:
2989 pass_ipa_inline (gcc::context *ctxt)
2990 : ipa_opt_pass_d (pass_data_ipa_inline, ctxt,
2991 NULL, /* generate_summary */
2992 NULL, /* write_summary */
2993 NULL, /* read_summary */
2994 NULL, /* write_optimization_summary */
2995 NULL, /* read_optimization_summary */
2996 NULL, /* stmt_fixup */
2997 0, /* function_transform_todo_flags_start */
2998 inline_transform, /* function_transform */
2999 NULL) /* variable_transform */
3002 /* opt_pass methods: */
3003 virtual unsigned int execute (function *) { return ipa_inline (); }
3005 }; // class pass_ipa_inline
3007 } // anon namespace
3009 ipa_opt_pass_d *
3010 make_pass_ipa_inline (gcc::context *ctxt)
3012 return new pass_ipa_inline (ctxt);